Broadcast signal transmitting apparatus, broadcast signal receiving apparatus, broadcast signal transmitting method and broadcast signal receiving method

ABSTRACT

Provided is a method for transmitting a broadcast signal. The method for transmitting a broadcast signal, according to the present invention, can be a broadcast content transmitting method, comprising the steps of: generating, by a first module, a first media stream for broadcast content wherein the first media stream includes a plurality of packets, and at least one of the packets includes time information; generating, by a second module, a second media stream for the broadcast content; transmitting, by a third module, the first media stream through a broadcast network; receiving, by a fourth module, a request for the second media stream from a receiver; and transmitting, by the fourth module, the second media stream to the receiver through the Internet network.

TECHNICAL FIELD

The present invention relates to a method and apparatus for transmittingand receiving broadcast signals.

BACKGROUND ART

As analog broadcast signal transmission comes to an end, varioustechnologies for transmitting/receiving digital broadcast signals arebeing developed. A digital broadcast signal may include a larger amountof video/audio data than an analog broadcast signal and may furtherinclude various types of additional data.

DISCLOSURE Technical Problem

That is, a digital broadcast system can provide HD (high definition)images, multi-channel audio and various additional services. However,data transmission efficiency for transmission of large amounts of data,robustness of transmission/reception networks and network flexibility inconsideration of mobile reception equipment need to be improved fordigital broadcast.

Technical Solution

The object of the present invention can be achieved by providing amethod for transmitting broadcast content, the method includinggenerating a first media stream of broadcast content by a first module,the first media stream including a plurality of packets and at least oneof the packets including time information, generating a second mediastream of the broadcast content by a second module, transmitting thefirst media stream through a broadcast network by a third module,receiving a request for the second media stream from a receiver by afourth module, and transmitting the second media stream to a receiverthrough the Internet by the fourth module.

The at least one packet may include an extension header including thetime information, and the time information may include timestampinformation indicating presentation time of the first media stream.

The extension header may include only a portion of the timestamp.

The extension header may further include timestamp informationindicating presentation time of the second media stream.

The extension header may further include information on suggestedpresentation delay up to consumption time from generating time of thefirst media stream.

The timestamp indicating presentation time of the first media stream mayindicate a presentation time value of the first media stream to whichthe suggested presentation delay is applied.

A payload of the at least one packet may include first timelinereference information for configuring a timeline of the first mediastream and second timeline reference information for configuring atimeline of the second media stream.

The payload of the at least one packet may further include informationon suggested presentation delay up to consumption time of generatingtime of the first media stream and the second media stream.

The first timeline reference information and the second timelinereference information may have a value to which the suggestedpresentation delay is applied.

The first media stream may be a video stream of the broadcast content,and the second media stream may be an audio stream of the broadcastcontent.

In another aspect of the present invention, provided herein is anapparatus for transmitting broadcast content, the apparatus including afirst module configured to generate a first media stream of broadcastcontent, the first media stream including a plurality of packets and atleast one of the packets including time information, a second moduleconfigured to generate a second media stream of the broadcast content, athird module configured to transmit the first media stream through abroadcast network, and a fourth module configured to receive a requestfor the second media stream from a receiver and to transmit the secondmedia stream to a receiver through the Internet.

The at least one packet may include an extension header including thetime information, and the time information may include timestampinformation indicating presentation time of the first media stream.

The extension header may include only a portion of the timestamp.

The extension header may further include timestamp informationindicating presentation time of the second media stream.

The extension header may further include information on suggestedpresentation delay up to consumption time from generating time of thefirst media stream.

The timestamp indicating presentation time of the first media stream mayindicate a presentation time value of the first media stream to whichthe suggested presentation delay is applied.

A payload of the at least one packet may include first timelinereference information for configuring a timeline of the first mediastream and second timeline reference information for configuring atimeline of the second media stream.

The payload of the at least one packet may further include informationon suggested presentation delay up to consumption time of generatingtime of the first media stream and the second media stream.

The first timeline reference information and the second timelinereference information may have a value to which the suggestedpresentation delay is applied.

The first media stream may be a video stream of the broadcast content,and the second media stream may be an audio stream of the broadcastcontent.

Advantageous Effects

An embodiment of the present invention provides a broadcast service bycontrolling QoS (Quality of Service) of each service or servicecomponent and by processing data according to features of each service.

An embodiment of the present invention provides a transmissionflexibility by transmitting various broadcast services through the sameRF (radio frequency) signal bandwidth.

An embodiment of the present invention enhances Robustness of abroadcast signal and an efficiency of a data transmission by using MIMO(Multiple Input Multiple Output) system.

An embodiment of the present invention provides a broadcast transmissionapparatus, an operation method of the broadcast transmission apparatus,a broadcast reception apparatus, and an operation method of thebroadcast reception apparatus that are capable of acquiring digitalbroadcast signals without errors although we are using mobile receivingapparatus or we are in door.

DESCRIPTION OF DRAWINGS

The accompanying drawings, which are included to provide a furtherunderstanding of the invention and are incorporated in and constitute apart of this application, illustrate embodiment(s) of the invention andtogether with the description serve to explain the principle of theinvention. In the drawings:

FIG. 1 illustrates a structure of an apparatus for transmittingbroadcast signals for future broadcast services according to anembodiment of the present invention.

FIG. 2 illustrates an input formatting block according to one embodimentof the present invention.

FIG. 3 illustrates an input formatting block according to anotherembodiment of the present invention.

FIG. 4 illustrates a BICM block according to an embodiment of thepresent invention.

FIG. 5 illustrates a BICM block according to another embodiment of thepresent invention.

FIG. 6 illustrates a frame building block according to one embodiment ofthe present invention.

FIG. 7 illustrates an OFDM generation block according to an embodimentof the present invention.

FIG. 8 illustrates a structure of an apparatus for receiving broadcastsignals for future broadcast services according to an embodiment of thepresent invention.

FIG. 9 illustrates a frame structure according to an embodiment of thepresent invention.

FIG. 10 illustrates a signaling hierarchy structure of the frameaccording to an embodiment of the present invention.

FIG. 11 illustrates preamble signaling data according to an embodimentof the present invention.

FIG. 12 illustrates PLS1 data according to an embodiment of the presentinvention.

FIG. 13 illustrates PLS2 data according to an embodiment of the presentinvention.

FIG. 14 illustrates PLS2 data according to another embodiment of thepresent invention.

FIG. 15 illustrates a logical structure of a frame according to anembodiment of the present invention.

FIG. 16 illustrates PLS mapping according to an embodiment of thepresent invention.

FIG. 17 illustrates EAC mapping according to an embodiment of thepresent invention.

FIG. 18 illustrates FIC mapping according to an embodiment of thepresent invention.

FIG. 19 illustrates an FEC structure according to an embodiment of thepresent invention.

FIG. 20 illustrates a time interleaving according to an embodiment ofthe present invention.

FIG. 21 illustrates the basic operation of a twisted row-column blockinterleaver according to an embodiment of the present invention.

FIG. 22 illustrates an operation of a twisted row-column blockinterleaver according to another embodiment of the present invention.

FIG. 23 illustrates a diagonal-wise reading pattern of a twistedrow-column block interleaver according to an embodiment of the presentinvention.

FIG. 24 illustrates interlaved XFECBLOCKs from each interleaving arrayaccording to an embodiment of the present invention.

FIG. 25 illustrates a data processing time when a File Delivery overUnidirectional Transport (FLUTE) protocol is used.

FIG. 26 illustrates a Real-Time Object Delivery over UnidirectionalTransport (ROUTE) protocol stack according to an embodiment of thepresent invention.

FIG. 27 illustrates a data structure of file-based multimedia contentaccording to an embodiment of the present invention.

FIG. 28 illustrates a media segment structure of MPEG-DASH to which thedata structure is applied.

FIG. 29 illustrates a data processing time using a ROUTE protocolaccording to an embodiment of the present invention.

FIG. 30 illustrates a Layered Coding Transport (LCT) packet structurefor file transmission according to an embodiment of the presentinvention.

FIG. 31 illustrates a structure of an LCT packet according to anotherembodiment of the present invention.

FIG. 32 illustrates real-time broadcast support information signalingbased on FDT according to an embodiment of the present invention.

FIG. 33 is a block diagram illustrating a broadcast signal transmissionapparatus according to an embodiment of the present invention.

FIG. 34 is a block diagram illustrating a broadcast signal transmissionapparatus according to an embodiment of the present invention.

FIG. 35 is a flowchart illustrating a process for generating andtransmitting in real time the file-based multimedia content according toan embodiment of the present invention.

FIG. 36 is a flowchart illustrating a process for allowing the broadcastsignal transmission apparatus to generate packets using a packetizeraccording to an embodiment of the present invention.

FIG. 37 is a flowchart illustrating a process forgenerating/transmitting in real time the file-based multimedia contentaccording to another embodiment of the present invention.

FIG. 38 is a block diagram illustrating a file-based multimedia contentreceiver according to an embodiment of the present invention.

FIG. 39 is a block diagram illustrating a file-based multimedia contentreceiver according to an embodiment of the present invention.

FIG. 40 is a flowchart illustrating a process for receiving/consuming afile-based multimedia content according to an embodiment of the presentinvention.

FIG. 41 is a flowchart illustrating a process for receiving/consuming inreal time a file-based multimedia content according to anotherembodiment of the present invention.

FIG. 42 is a diagram illustrating a structure of a packet includingobject type information according to another embodiment of the presentinvention.

FIG. 43 is a diagram illustrating a structure of a packet includingobject type information according to another embodiment of the presentinvention.

FIG. 44 is a diagram illustrating a structure of a broadcast signalreceiving apparatus using object type information according to anotherembodiment of the present invention.

FIG. 45 is a diagram illustrating a structure of a broadcast signalreceiving apparatus using object type information according to anotherembodiment of the present invention.

FIG. 46 is a diagram illustrating a structure of a packet including typeinformation according to another embodiment of the present invention.

FIG. 47 is a diagram illustrating a structure of a packet includingboundary information according to another embodiment of the presentinvention.

FIG. 48 is a diagram illustrating a structure of a packet includingmapping information according to another embodiment of the presentinvention.

FIG. 49 is a diagram illustrating a structure of an LCT packet includinggrouping information according to another embodiment of the presentinvention.

FIG. 50 is a diagram illustrating grouping of a session and an objectaccording to another embodiment of the present invention.

FIG. 51 is a diagram illustrating a structure of a broadcast signaltransmitting apparatus using packet information according to anotherembodiment of the present invention.

FIG. 52 is a diagram illustrating a structure of a broadcast signalreceiving apparatus according to another embodiment of the presentinvention.

FIG. 53 is a diagram illustrating a structure of a broadcast signalreceiving apparatus using packet information according to anotherembodiment of the present invention.

FIG. 54 is a diagram illustrating a structure of a broadcast signalreceiving apparatus using packet information according to anotherembodiment of the present invention.

FIG. 55 is a diagram illustrating a structure of a broadcast signalreceiving apparatus using packet information according to anotherembodiment of the present invention.

FIG. 56 is a diagram showing the structure of a packet includingpriority information according to another embodiment of the presentinvention.

FIG. 57 is a diagram showing the structure of a packet includingpriority information according to another embodiment of the presentinvention.

FIG. 58 is a diagram showing the structure of a packet including offsetinformation according to another embodiment of the present invention.

FIG. 59 is a diagram showing the structure of a packet including randomaccess point (RAP) information according to another embodiment of thepresent invention.

FIG. 60 is a diagram showing the structure of a packet including randomaccess point (RAP) information according to another embodiment of thepresent invention.

FIG. 61 is a diagram showing the structure of a packet including realtime information according to another embodiment of the presentinvention.

FIG. 62 is a diagram showing the structure of a broadcast signaltransmission apparatus according to another embodiment of the presentinvention.

FIG. 63 is a diagram showing the structure of a broadcast signalreception apparatus according to another embodiment of the presentinvention.

FIG. 64 is a view showing a protocol stack for a next generationbroadcasting system according to an embodiment of the present invention.

FIG. 65 illustrates a receiver of a next generation broadcasting systemaccording to an embodiment of the present invention.

FIG. 66 is a view showing a broadcast receiver according to anembodiment of the present invention.

FIG. 67 illustrates a timeline component for synchronization between atransport stream in the broadcasting network and a transport stream inthe Internet (heterogeneous network) according to an embodiment of thepresent invention.

FIG. 68 illustrates syntax of the timeline component AU according to anembodiment of the present invention.

FIG. 69 illustrates syntax of the timeline component AU according toanother embodiment of the present invention.

FIG. 70 illustrates a scheme of synchronizing a stream transmittedthrough a heterogeneous network (for example, the Internet) with astream transmitted through the broadcasting network using a timelinecomponent when a timestamp of a broadcasting network transmission packetis absent according to an embodiment of the present invention.

FIG. 71 illustrates syntax of the timeline component AU according toanother embodiment of the present invention.

FIG. 72 illustrates syntax of the timeline component AU according toanother embodiment of the present invention.

FIG. 73 illustrates a method of synchronization between a streamtransmitted over a broadcast network and a stream transmitted over aheterogeneous network using timeline reference signaling informationaccording to another embodiment of the present invention.

FIG. 74 illustrates a syntax of a timeline reference information AUaccording to another embodiment of the present invention.

FIG. 75 illustrates a syntax of a timeline reference information AUaccording to another embodiment of the present invention.

FIG. 76 illustrates the structure of an LCT packet supportingtransmission of timeline reference information according to anotherembodiment of the present invention.

FIG. 77 illustrates the structure of an LCT packet supportingtransmission of timeline reference information according to anotherembodiment of the present invention.

FIG. 78 illustrates a synchronization scheme using the timelinecomponent AU between a transport stream in the broadcasting network towhich DASH is applied and a transport stream in a heterogeneous network(for example, the Internet) according to an embodiment of the presentinvention.

FIG. 79 illustrates the sample entry for identifying a timelinecomponent in the ISO BMFF according to an embodiment of the presentinvention.

FIG. 80 illustrates a track reference type box for expressing adependency relation between a timeline component track and another trackin the ISO BMFF according to an embodiment of the present invention.

FIG. 81 illustrates a configuration for acquiring a service and/orcontent in the next generation broadcasting system according to anembodiment of the present invention.

FIG. 82 illustrates a scheme of accessing video data and/or audio datain the ISO BMFF according to an embodiment of the present invention.

FIG. 83 illustrates a scheme of accessing video data and/or audio datain the ISO BMFF according to another embodiment of the presentinvention.

FIG. 84 is a view illustrating a broadcast transmission frame accordingto an embodiment of the present invention.

FIG. 85 is a view of a broadcast transmission frame according to anotherembodiment of the present invention.

FIG. 86 is a view illustrating a structure of a transport packettransmitting a broadcast service according to an embodiment of thepresent invention.

FIG. 87 is a view illustrating a value of a network_protocol fieldincluded in a transport packet for transmitting a broadcast serviceaccording to an embodiment of the present invention.

FIG. 88 is a view that a broadcast service signaling table and broadcastservice transmission path signaling information signal broadcast serviceand a broadcast service transmission path.

FIG. 89 is a view illustrating a broadcast service signaling tableaccording to an embodiment of the present invention.

FIG. 90 is a view illustrating a value of a service_category fieldincluded in a broadcast service signaling table according to anembodiment of the present invention.

FIG. 91 shows a broadcast service signaling table according to anembodiment of the present invention.

FIG. 92 is a view of a stream identifier descriptor according to anotherembodiment of the present invention.

FIG. 93 is a view illustrating an operation when a broadcasttransmission device transmits a broadcast service signaling tableaccording to an embodiment of the present invention.

FIG. 94 is a view illustrating an operation when a broadcast receptiondevice receives a packetized broadcast packet according to an embodimentof the present invention.

FIG. 95 is a view illustrating a segment configuration according to anembodiment of the present invention.

FIG. 96 is a view illustrating a structure of a real-time transportprotocol (RTP) packet for real-time content transmission according to anembodiment of the present invention.

FIG. 97 is a view illustrating a media file format based on an ISO basemedia file format (ISO BMFF) according to an embodiment of the presentinvention.

FIG. 98 is a view illustrating a configuration of a payload header in apacket payload according to an embodiment of the present invention.

FIGS. 99 and 100 are views illustrating a payload configuration of atransport packet in which one media data is packetized in one packet.

FIGS. 101 and 102 are views illustrating a configuration of a transportpacket in which a plurality of media data are packetized in one packet.

FIG. 103 is a view illustrating the payload of a fragmented packetaccording to an embodiment of the present invention.

FIG. 104 is a view illustrating a configuration of a payload in afragmented packet according to another embodiment of the presentinvention.

FIG. 105 is a view when a broadcast transmission device fragments an ISOBMFF based media file into a plurality of packets.

FIG. 106 is a view illustrating first fragmentation unit data packetizedby the broadcast transmission device of FIG. 105.

FIGS. 107 to 109 are views illustrating a fragmentation unit includingremaining data except for the start data in the fragmentation unit dataof FIG. 105 according to an embodiment of the present invention.

FIG. 110 is a view illustrating a timeline signaling table of metadataaccording to an embodiment of the present invention.

FIG. 111 is a view illustrating a configuration of payload data in whichone metadata is packetized in payload data of a transport packet.

FIG. 112 is a view when payload data of a transport packet includesmetadata for a timeline according to an embodiment of the presentinvention.

FIG. 113 is a view when a plurality of metadata are packetized in onetransport packet.

FIG. 114 is a view when one transport packet includes several timelineinformation.

FIG. 115 is a view illustrating a packet payload in which one metadatais divided and packetized in a plurality of transport packets.

FIG. 116 is a view illustrating a metadata fragment header according toanother embodiment of the present invention.

FIG. 117 is a view illustrating an operation when a broadcast receptiondevice receives a broadcast packet according to an embodiment of thepresent invention.

FIG. 118 is a view when video stream is transmitted using RTP throughbroadcast network and video stream is transmitted using file formatbased media data through an internet network.

FIG. 119 is a view illustrating a configuration of a transport packetaccording to an embodiment of the present invention.

FIG. 120 is a view illustrating a configuration of a packet headeraccording to an embodiment of the present invention.

FIGS. 121 and 122 are views illustrating a configuration of a headerextension including time information.

FIGS. 123 to 126 are views illustrating a configuration of a headerextension according to another embodiment of the present invention.

FIG. 127 is a view illustrating a structure of a header extension forsupporting mapping with another timing information according to anembodiment of the present invention.

FIG. 128 is a view illustrating a method of operating a broadcasttransmission device according to an embodiment of the present invention.

FIG. 129 is a view illustrating a method of operating a broadcastreception device according to an embodiment of the present invention.

FIG. 130 is a view illustrating a structure of a packet header includinginformation on a configuration of a transport packet.

FIG. 131 is a view illustrating a configuration of the transport packetdescribed with reference to FIG. 130.

FIG. 132 is a view illustrating a method of operating a broadcasttransmission device according to an embodiment of the present invention.

FIG. 133 is a view illustrating a method of operating a broadcastreception device according to an embodiment of the present invention.

FIG. 134 is a view illustrating timeline reference information AUincluding suggested presentation delay (SPD) according to an embodimentof the present invention.

FIG. 135 is a view illustrating timeline reference information AUincluding suggested presentation delay (SPD) according to anotherembodiment of the present invention.

FIG. 136 is a view illustrating an LCT packet structure includingsuggested presentation delay (SPD) according to an embodiment of thepresent invention.

FIG. 137 is a view illustrating an LCT packet structure includingsuggested presentation delay (SPD) according to another embodiment ofthe present invention.

FIG. 138 is a view illustrating an LCT packet structure includingsuggested presentation delay (SPD) according to another embodiment ofthe present invention.

FIG. 139 is a diagram illustrating an extension part of an LCT packetstructure including Suggested Presentation Delay (SPD) according toanother embodiment of the present invention.

FIG. 140 is a diagram illustrating an extension part of an LCT packetstructure including Suggested Presentation Delay (SPD) according toanother embodiment of the present invention.

FIG. 141 is a diagram illustrating an extension part of an LCT packetstructure including Suggested Presentation Delay (SPD) according toanother embodiment of the present invention.

FIG. 142 is a diagram illustrating an extension part of an LCT packetstructure including Suggested Presentation Delay (SPD) according toanother embodiment of the present invention.

FIG. 143 is a diagram illustrating an extension part of an LCT packetstructure including Suggested Presentation Delay (SPD) according toanother embodiment of the present invention.

FIG. 144 is a diagram illustrating a method of transmitting broadcastcontent according to an embodiment of the present invention.

FIG. 145 is a diagram illustrating an apparatus for transmittingbroadcast content according to an embodiment of the present invention.

BEST MODE

Reference will now be made in detail to the preferred embodiments of thepresent invention, examples of which are illustrated in the accompanyingdrawings. The detailed description, which will be given below withreference to the accompanying drawings, is intended to explain exemplaryembodiments of the present invention, rather than to show the onlyembodiments that can be implemented according to the present invention.The following detailed description includes specific details in order toprovide a thorough understanding of the present invention. However, itwill be apparent to those skilled in the art that the present inventionmay be practiced without such specific details.

Although most terms used in the present invention have been selectedfrom general ones widely used in the art, some terms have beenarbitrarily selected by the applicant and their meanings are explainedin detail in the following description as needed. Thus, the presentinvention should be understood based upon the intended meanings of theterms rather than their simple names or meanings.

The present invention provides apparatuses and methods for transmittingand receiving broadcast signals for future broadcast services. Futurebroadcast services according to an embodiment of the present inventioninclude a terrestrial broadcast service, a mobile broadcast service, aUHDTV service, etc. The present invention may process broadcast signalsfor the future broadcast services through non-MIMO (Multiple InputMultiple Output) or MIMO according to one embodiment. A non-MIMO schemeaccording to an embodiment of the present invention may include a MISO(Multiple Input Single Output) scheme, a SISO (Single Input SingleOutput) scheme, etc.

While MISO or MIMO uses two antennas in the following for convenience ofdescription, the present invention is applicable to systems using two ormore antennas. The present invention may defines three physical layer(PL) profiles—base, handheld and advanced profiles—each optimized tominimize receiver complexity while attaining the performance requiredfor a particular use case. The physical layer (PHY) profiles are subsetsof all configurations that a corresponding receiver should implement.

The three PHY profiles share most of the functional blocks but differslightly in specific blocks and/or parameters. Additional PHY profilescan be defined in the future. For the system evolution, future profilescan also be multiplexed with the existing profiles in a single RFchannel through a future extension frame (FEF). The details of each PHYprofile are described below.

1. Base Profile

The base profile represents a main use case for fixed receiving devicesthat are usually connected to a roof-top antenna. The base profile alsoincludes portable devices that could be transported to a place butbelong to a relatively stationary reception category. Use of the baseprofile could be extended to handheld devices or even vehicular by someimproved implementations, but those use cases are not expected for thebase profile receiver operation.

Target SNR range of reception is from approximately 10 to 20 dB, whichincludes the 15 dB SNR reception capability of the existing broadcastsystem (e.g. ATSC A/53). The receiver complexity and power consumptionis not as critical as in the battery-operated handheld devices, whichwill use the handheld profile. Key system parameters for the baseprofile are listed in below table 1.

TABLE 1 LDPC codeword length 16K, 64K bits Constellation size 4~10 bpcu(bits per channel use) Time de-interleaving memory size ≦219 data cellsPilot patterns Pilot pattern for fixed reception FFT size 16K, 32Kpoints

2. Handheld Profile

The handheld profile is designed for use in handheld and vehiculardevices that operate with battery power. The devices can be moving withpedestrian or vehicle speed. The power consumption as well as thereceiver complexity is very important for the implementation of thedevices of the handheld profile. The target SNR range of the handheldprofile is approximately 0 to 10 dB, but can be configured to reachbelow 0 dB when intended for deeper indoor reception.

In addition to low SNR capability, resilience to the Doppler Effectcaused by receiver mobility is the most important performance attributeof the handheld profile. Key system parameters for the handheld profileare listed in the below table 2.

TABLE 2 LDPC codeword length 16K bits Constellation size 2~8 bpcu Timede-interleaving memory size ≦218 data cells Pilot patterns Pilotpatterns for mobile and indoor reception FFT size 8K, 16K points

3. Advanced Profile

The advanced profile provides highest channel capacity at the cost ofmore implementation complexity. This profile requires using MIMOtransmission and reception, and UHDTV service is a target use case forwhich this profile is specifically designed. The increased capacity canalso be used to allow an increased number of services in a givenbandwidth, e.g., multiple SDTV or HDTV services.

The target SNR range of the advanced profile is approximately 20 to 30dB. MIMO transmission may initially use existing elliptically-polarizedtransmission equipment, with extension to full-power cross-polarizedtransmission in the future. Key system parameters for the advancedprofile are listed in below table 3.

TABLE 3 LDPC codeword length 16K, 64K bits Constellation size 8~12 bpcuTime de-interleaving memory size ≦219 data cells Pilot patterns Pilotpattern for fixed reception FFT size 16K, 32K points

In this case, the base profile can be used as a profile for both theterrestrial broadcast service and the mobile broadcast service. That is,the base profile can be used to define a concept of a profile whichincludes the mobile profile. Also, the advanced profile can be dividedadvanced profile for a base profile with MIMO and advanced profile for ahandheld profile with MIMO. Moreover, the three profiles can be changedaccording to intention of the designer.

The following terms and definitions may apply to the present invention.The following terms and definitions can be changed according to design.

auxiliary stream: sequence of cells carrying data of as yet undefinedmodulation and coding, which may be used for future extensions or asrequired by broadcasters or network operators

base data pipe: data pipe that carries service signaling data

baseband frame (or BBFRAME): set of Kbch bits which form the input toone FEC encoding process (BCH and LDPC encoding)

cell: modulation value that is carried by one carrier of the OFDMtransmission

coded block: LDPC-encoded block of PLS1 data or one of the LDPC-encodedblocks of PLS2 data

data pipe: logical channel in the physical layer that carries servicedata or related metadata, which may carry one or multiple service(s) orservice component(s).

data pipe unit: a basic unit for allocating data cells to a DP in aframe.

data symbol: OFDM symbol in a frame which is not a preamble symbol (theframe signaling symbol and frame edge symbol is included in the datasymbol)

DP_ID: this 8-bit field identifies uniquely a DP within the systemidentified by the SYSTEM_ID

dummy cell: cell carrying a pseudo-random value used to fill theremaining capacity not used for PLS signaling, DPs or auxiliary streams

emergency alert channel: part of a frame that carries EAS informationdata

frame: physical layer time slot that starts with a preamble and endswith a frame edge symbol

frame repetition unit: a set of frames belonging to same or differentphysical layer profile including a FEF, which is repeated eight times ina super-frame

fast information channel: a logical channel in a frame that carries themapping information between a service and the corresponding base DP

FECBLOCK: set of LDPC-encoded bits of a DP data

FFT size: nominal FFT size used for a particular mode, equal to theactive symbol period Ts expressed in cycles of the elementary period T

frame signaling symbol: OFDM symbol with higher pilot density used atthe start of a frame in certain combinations of FFT size, guard intervaland scattered pilot pattern, which carries a part of the PLS data

frame edge symbol: OFDM symbol with higher pilot density used at the endof a frame in certain combinations of FFT size, guard interval andscattered pilot pattern

frame-group: the set of all the frames having the same PHY profile typein a super-frame.

future extension frame: physical layer time slot within the super-framethat could be used for future extension, which starts with a preamble

Futurecast UTB system: proposed physical layer broadcasting system, ofwhich the input is one or more MPEG2-TS or IP or general stream(s) andof which the output is an RF signal

input stream: A stream of data for an ensemble of services delivered tothe end users by the system.

normal data symbol: data symbol excluding the frame signaling symbol andthe frame edge symbol

PHY profile: subset of all configurations that a corresponding receivershould implement

PLS: physical layer signaling data consisting of PLS1 and PLS2

PLS1: a first set of PLS data carried in the FSS symbols having a fixedsize, coding and modulation, which carries basic information about thesystem as well as the parameters needed to decode the PLS2

NOTE: PLS1 data remains constant for the duration of a frame-group.

PLS2: a second set of PLS data transmitted in the FSS symbol, whichcarries more detailed PLS data about the system and the DPs

PLS2 dynamic data: PLS2 data that may dynamically change frame-by-frame

PLS2 static data: PLS2 data that remains static for the duration of aframe-group

preamble signaling data: signaling data carried by the preamble symboland used to identify the basic mode of the system

preamble symbol: fixed-length pilot symbol that carries basic PLS dataand is located in the beginning of a frame

NOTE: The preamble symbol is mainly used for fast initial band scan todetect the system signal, its timing, frequency offset, and FFT-size.

reserved for future use: not defined by the present document but may bedefined in future

super-frame: set of eight frame repetition units

time interleaving block (TI block): set of cells within which timeinterleaving is carried out, corresponding to one use of the timeinterleaver memory

TI group: unit over which dynamic capacity allocation for a particularDP is carried out, made up of an integer, dynamically varying number ofXFECBLOCKs

NOTE: The TI group may be mapped directly to one frame or may be mappedto multiple frames. It may contain one or more TI blocks.

Type 1 DP: DP of a frame where all DPs are mapped into the frame in TDMfashion

Type 2 DP: DP of a frame where all DPs are mapped into the frame in FDMfashion

XFECBLOCK: set of Ncells cells carrying all the bits of one LDPCFECBLOCK

FIG. 1 illustrates a structure of an apparatus for transmittingbroadcast signals for future broadcast services according to anembodiment of the present invention.

The apparatus for transmitting broadcast signals for future broadcastservices according to an embodiment of the present invention can includean input formatting block 1000, a BICM (Bit interleaved coding &modulation) block 1010, a frame building block 1020, an OFDM (OrthogonalFrequency Division Multiplexing) generation block 1030 and a signalinggeneration block 1040. A description will be given of the operation ofeach module of the apparatus for transmitting broadcast signals.

IP stream/packets and MPEG2-TS are the main input formats, other streamtypes are handled as General Streams. In addition to these data inputs,Management Information is input to control the scheduling and allocationof the corresponding bandwidth for each input stream. One or multiple TSstream(s), IP stream(s) and/or General Stream(s) inputs aresimultaneously allowed.

The input formatting block 1000 can demultiplex each input stream intoone or multiple data pipe(s), to each of which an independent coding andmodulation is applied. The data pipe (DP) is the basic unit forrobustness control, thereby affecting quality-of-service (QoS). One ormultiple service(s) or service component(s) can be carried by a singleDP. Details of operations of the input formatting block 1000 will bedescribed later.

The data pipe is a logical channel in the physical layer that carriesservice data or related metadata, which may carry one or multipleservice(s) or service component(s).

Also, the data pipe unit: a basic unit for allocating data cells to a DPin a frame.

In the BICM block 1010, parity data is added for error correction andthe encoded bit streams are mapped to complex-value constellationsymbols. The symbols are interleaved across a specific interleavingdepth that is used for the corresponding DP. For the advanced profile,MIMO encoding is performed in the BICM block 1010 and the additionaldata path is added at the output for MIMO transmission. Details ofoperations of the BICM block 1010 will be described later.

The Frame Building block 1020 can map the data cells of the input DPsinto the OFDM symbols within a frame. After mapping, the frequencyinterleaving is used for frequency-domain diversity, especially tocombat frequency-selective fading channels. Details of operations of theFrame Building block 1020 will be described later.

After inserting a preamble at the beginning of each frame, the OFDMGeneration block 1030 can apply conventional OFDM modulation having acyclic prefix as guard interval. For antenna space diversity, adistributed MISO scheme is applied across the transmitters. In addition,a Peak-to-Average Power Reduction (PAPR) scheme is performed in the timedomain. For flexible network planning, this proposal provides a set ofvarious FFT sizes, guard interval lengths and corresponding pilotpatterns. Details of operations of the OFDM Generation block 1030 willbe described later.

The Signaling Generation block 1040 can create physical layer signalinginformation used for the operation of each functional block. Thissignaling information is also transmitted so that the services ofinterest are properly recovered at the receiver side. Details ofoperations of the Signaling Generation block 1040 will be describedlater.

FIGS. 2, 3 and 4 illustrate the input formatting block 1000 according toembodiments of the present invention. A description will be given ofeach figure.

FIG. 2 illustrates an input formatting block according to one embodimentof the present invention. FIG. 2 shows an input formatting module whenthe input signal is a single input stream.

The input formatting block illustrated in FIG. 2 corresponds to anembodiment of the input formatting block 1000 described with referenceto FIG. 1.

The input to the physical layer may be composed of one or multiple datastreams. Each data stream is carried by one DP. The mode adaptationmodules slice the incoming data stream into data fields of the basebandframe (BBF). The system supports three types of input data streams:MPEG2-TS, Internet protocol (IP) and Generic stream (GS). MPEG2-TS ischaracterized by fixed length (188 byte) packets with the first bytebeing a sync-byte (0x47). An IP stream is composed of variable length IPdatagram packets, as signaled within IP packet headers. The systemsupports both IPv4 and IPv6 for the IP stream. GS may be composed ofvariable length packets or constant length packets, signaled withinencapsulation packet headers.

(a) shows a mode adaptation block 2000 and a stream adaptation 2010 forsignal DP and (b) shows a PLS generation block 2020 and a PLS scrambler2030 for generating and processing PLS data. A description will be givenof the operation of each block.

The Input Stream Splitter splits the input TS, IP, GS streams intomultiple service or service component (audio, video, etc.) streams. Themode adaptation module 2010 is comprised of a CRC Encoder, BB (baseband)Frame Slicer, and BB Frame Header Insertion block.

The CRC Encoder provides three kinds of CRC encoding for error detectionat the user packet (UP) level, i.e., CRC-8, CRC-16, and CRC-32. Thecomputed CRC bytes are appended after the UP. CRC-8 is used for TSstream and CRC-32 for IP stream. If the GS stream doesn't provide theCRC encoding, the proposed CRC encoding should be applied.

BB Frame Slicer maps the input into an internal logical-bit format. Thefirst received bit is defined to be the MSB. The BB Frame Slicerallocates a number of input bits equal to the available data fieldcapacity. To allocate a number of input bits equal to the BBF payload,the UP packet stream is sliced to fit the data field of BBF.

BB Frame Header Insertion block can insert fixed length BBF header of 2bytes is inserted in front of the BB Frame. The BBF header is composedof STUFFI (1 bit), SYNCD (13 bits), and RFU (2 bits). In addition to thefixed 2-Byte BBF header, BBF can have an extension field (1 or 3 bytes)at the end of the 2-byte BBF header.

The stream adaptation 2010 is comprised of stuffing insertion block andBB scrambler. The stuffing insertion block can insert stuffing fieldinto a payload of a BB frame. If the input data to the stream adaptationis sufficient to fill a BB-Frame, STUFFI is set to ‘0’ and the BBF hasno stuffing field. Otherwise STUFFI is set to ‘I’ and the stuffing fieldis inserted immediately after the BBF header. The stuffing fieldcomprises two bytes of the stuffing field header and a variable size ofstuffing data.

The BB scrambler scrambles complete BBF for energy dispersal. Thescrambling sequence is synchronous with the BBF. The scrambling sequenceis generated by the feed-back shift register.

The PLS generation block 2020 can generate physical layer signaling(PLS) data. The PLS provides the receiver with a means to accessphysical layer DPs. The PLS data consists of PLS1 data and PLS2 data.

The PLS1 data is a first set of PLS data carried in the FSS symbols inthe frame having a fixed size, coding and modulation, which carriesbasic information about the system as well as the parameters needed todecode the PLS2 data. The PLS1 data provides basic transmissionparameters including parameters required to enable the reception anddecoding of the PLS2 data. Also, the PLS1 data remains constant for theduration of a frame-group.

The PLS2 data is a second set of PLS data transmitted in the FSS symbol,which carries more detailed PLS data about the system and the DPs. ThePLS2 contains parameters that provide sufficient information for thereceiver to decode the desired DP. The PLS2 signaling further consistsof two types of parameters, PLS2 Static data (PLS2-STAT data) and PLS2dynamic data (PLS2-DYN data). The PLS2 Static data is PLS2 data thatremains static for the duration of a frame-group and the PLS2 dynamicdata is PLS2 data that may dynamically change frame-by-frame.

Details of the PLS data will be described later.

The PLS scrambler 2030 can scramble the generated PLS data for energydispersal.

The above-described blocks may be omitted or replaced by blocks havingsimilar or identical functions.

FIG. 3 illustrates an input formatting block according to anotherembodiment of the present invention.

The input formatting block illustrated in FIG. 3 corresponds to anembodiment of the input formatting block 1000 described with referenceto FIG. 1.

FIG. 3 shows a mode adaptation block of the input formatting block whenthe input signal corresponds to multiple input streams.

The mode adaptation block of the input formatting block for processingthe multiple input streams can independently process the multiple inputstreams.

Referring to FIG. 3, the mode adaptation block for respectivelyprocessing the multiple input streams can include an input streamsplitter 3000, an input stream synchronizer 3010, a compensating delayblock 3020, a null packet deletion block 3030, a head compression block3040, a CRC encoder 3050, a BB frame slicer 3060 and a BB headerinsertion block 3070. Description will be given of each block of themode adaptation block.

Operations of the CRC encoder 3050, BB frame slicer 3060 and BB headerinsertion block 3070 correspond to those of the CRC encoder, BB frameslicer and BB header insertion block described with reference to FIG. 2and thus description thereof is omitted.

The input stream splitter 3000 can split the input TS, IP, GS streamsinto multiple service or service component (audio, video, etc.) streams.

The input stream synchronizer 3010 may be referred as ISSY. The ISSY canprovide suitable means to guarantee Constant. Bit Rate (CBR) andconstant end-to-end transmission delay for any input data format. TheISSY is always used for the case of multiple DPs carrying TS, andoptionally used for multiple DPs carrying GS streams.

The compensating delay block 3020 can delay the split TS packet streamfollowing the insertion of ISSY information to allow a TS packetrecombining mechanism without requiring additional memory in thereceiver.

The null packet deletion block 3030, is used only for the TS inputstream case. Some TS input streams or split TS streams may have a largenumber of null-packets present in order to accommodate VBR (variablebit-rate) services in a CBR TS stream. In this case, in order to avoidunnecessary transmission overhead, null-packets can be identified andnot transmitted. In the receiver, removed null-packets can bere-inserted in the exact place where they were originally by referenceto a deleted null-packet (DNP) counter that is inserted in thetransmission, thus guaranteeing constant bit-rate and avoiding the needfor time-stamp (PCR) updating.

The head compression block 3040 can provide packet header compression toincrease transmission efficiency for TS or IP input streams. Because thereceiver can have a priori information on certain parts of the header,this known information can be deleted in the transmitter.

For Transport Stream, the receiver has a-priori information about thesync-byte configuration (0x47) and the packet length (188 Byte). If theinput TS stream carries content that has only one PID, i.e., for onlyone service component (video, audio, etc.) or service sub-component (SVCbase layer, SVC enhancement layer, MVC base view or MVC dependentviews), TS packet header compression can be applied (optionally) to theTransport Stream. IP packet header compression is used optionally if theinput steam is an IP stream. The above-described blocks may be omittedor replaced by blocks having similar or identical functions.

FIG. 4 illustrates a BICM block according to an embodiment of thepresent invention.

The BICM block illustrated in FIG. 4 corresponds to an embodiment of theBICM block 1010 described with reference to FIG. 1.

As described above, the apparatus for transmitting broadcast signals forfuture broadcast services according to an embodiment of the presentinvention can provide a terrestrial broadcast service, mobile broadcastservice, UHDTV service, etc.

Since QoS (quality of service) depends on characteristics of a serviceprovided by the apparatus for transmitting broadcast signals for futurebroadcast services according to an embodiment of the present invention,data corresponding to respective services needs to be processed throughdifferent schemes. Accordingly, the a BICM block according to anembodiment of the present invention can independently process DPs inputthereto by independently applying SISO, MISO and MIMO schemes to thedata pipes respectively corresponding to data paths. Consequently, theapparatus for transmitting broadcast signals for future broadcastservices according to an embodiment of the present invention can controlQoS for each service or service component transmitted through each DP.

(a) shows the BICM block shared by the base profile and the handheldprofile and (b) shows the BICM block of the advanced profile.

The BICM block shared by the base profile and the handheld profile andthe BICM block of the advanced profile can include plural processingblocks for processing each DP.

A description will be given of each processing block of the BICM blockfor the base profile and the handheld profile and the BICM block for theadvanced profile.

A processing block 5000 of the BICM block for the base profile and thehandheld profile can include a Data FEC encoder 5010, a bit interleaver5020, a constellation mapper 5030, an SSD (Signal Space Diversity)encoding block 5040 and a time interleaver 5050.

The Data FEC encoder 5010 can perform the FEC encoding on the input BBFto generate FECBLOCK procedure using outer coding (BCH), and innercoding (LDPC). The outer coding (BCH) is optional coding method. Detailsof operations of the Data FEC encoder 5010 will be described later.

The bit interleaver 5020 can interleave outputs of the Data FEC encoder5010 to achieve optimized performance with combination of the LDPC codesand modulation scheme while providing an efficiently implementablestructure. Details of operations of the bit interleaver 5020 will bedescribed later.

The constellation mapper 5030 can modulate each cell word from the bitinterleaver 5020 in the base and the handheld profiles, or cell wordfrom the Cell-word demultiplexer 5010-1 in the advanced profile usingeither QPSK, QAM-16, non-uniform QAM (NUQ-64, NUQ-256, NUQ-1024) ornon-uniform constellation (NUC-16, NUC-64, NUC-256, NUC-1024) to give apower-normalized constellation point, el. This constellation mapping isapplied only for DPs. Observe that QAM-16 and NUQs are square shaped,while NUCs have arbitrary shape. When each constellation is rotated byany multiple of 90 degrees, the rotated constellation exactly overlapswith its original one. This “rotation-sense” symmetric property makesthe capacities and the average powers of the real and imaginarycomponents equal to each other. Both NUQs and NUCs are definedspecifically for each code rate and the particular one used is signaledby the parameter DP_MOD filed in PLS2 data.

The time interleaver 5050 can operates at the DP level. The parametersof time interleaving (TI) may be set differently for each DP. Details ofoperations of the time interleaver 5050 will be described later.

A processing block 5000-1 of the BICM block for the advanced profile caninclude the Data FEC encoder, bit interleaver, constellation mapper, andtime interleaver.

However, the processing block 5000-1 is distinguished from theprocessing block 5000 further includes a cell-word demultiplexer 5010-1and a MIMO encoding block 5020-1.

Also, the operations of the Data FEC encoder, bit interleaver,constellation mapper, and time interleaver in the processing block5000-1 correspond to those of the Data FEC encoder 5010, bit interleaver5020, constellation mapper 5030, and time interleaver 5050 described andthus description thereof is omitted.

The cell-word demultiplexer 5010-1 is used for the DP of the advancedprofile to divide the single cell-word stream into dual cell-wordstreams for MIMO processing. Details of operations of the cell-worddemultiplexer 5010-1 will be described later.

The MIMO encoding block 5020-1 can processing the output of thecell-word demultiplexer 5010-1 using MIMO encoding scheme. The MIMOencoding scheme was optimized for broadcasting signal transmission. TheMIMO technology is a promising way to get a capacity increase but itdepends on channel characteristics. Especially for broadcasting, thestrong LOS component of the channel or a difference in the receivedsignal power between two antennas caused by different signal propagationcharacteristics makes it difficult to get capacity gain from MIMO. Theproposed MIMO encoding scheme overcomes this problem using arotation-based pre-coding and phase randomization of one of the MIMOoutput signals.

MIMO encoding is intended for a 2×2 MIMO system requiring at least twoantennas at both the transmitter and the receiver. Two MIMO encodingmodes are defined in this proposal; full-rate spatial multiplexing(FR-SM) and full-rate full-diversity spatial multiplexing (FRFD-SM). TheFR-SM encoding provides capacity increase with relatively smallcomplexity increase at the receiver side while the FRFD-SM encodingprovides capacity increase and additional diversity gain with a greatcomplexity increase at the receiver side. The proposed MIMO encodingscheme has no restriction on the antenna polarity configuration.

MIMO processing is required for the advanced profile frame, which meansall DPs in the advanced profile frame are processed by the MIMO encoder.MIMO processing is applied at DP level. Pairs of the ConstellationMapper outputs NUQ (e1,i and e2,i) are fed to the input of the MIMOEncoder. Paired MIMO Encoder output (g1,i and g2,i) is transmitted bythe same carrier k and OFDM symbol 1 of their respective TX antennas.

The above-described blocks may be omitted or replaced by blocks havingsimilar or identical functions.

FIG. 5 illustrates a BICM block according to another embodiment of thepresent invention.

The BICM block illustrated in FIG. 6 corresponds to an embodiment of theBICM block 1010 described with reference to FIG. 1.

FIG. 5 illustrates a BICM block for protection of physical layersignaling (PLS), emergency alert channel (EAC) and fast informationchannel (FIC). EAC is a part of a frame that carries EAS informationdata and FIC is a logical channel in a frame that carries the mappinginformation between a service and the corresponding base DP. Details ofthe EAC and FIC will be described later.

Referring to FIG. 6, the BICM block for protection of PLS, EAC and FICcan include a PLS FEC encoder 6000, a bit interleaver 6010 and aconstellation mapper 6020.

Also, the PLS FEC encoder 6000 can include a scrambler, BCHencoding/zero insertion block, LDPC encoding block and LDPC paritypuncturing block. Description will be given of each block of the BICMblock.

The PLS FEC encoder 6000 can encode the scrambled PLS 1/2 data, EAC andFIC section.

The scrambler can scramble PLS1 data and PLS2 data before BCH encodingand shortened and punctured LDPC encoding.

The BCH encoding/zero insertion block can perform outer encoding on thescrambled PLS 1/2 data using the shortened BCH code for PLS protectionand insert zero bits after the BCH encoding. For PLS1 data only, theoutput bits of the zero insertion may be permutted before LDPC encoding.

The LDPC encoding block can encode the output of the BCH encoding/zeroinsertion block using LDPC code. To generate a complete coded block,Cldpc, parity bits, Pldpc are encoded systematically from eachzero-inserted PLS information block, Ildpc and appended after it.

C _(ldpc) =[I _(ldpc) P _(ldpc) ]=[i ₀ ,i ₁ , . . . ,i _(K) _(ldpc) ⁻¹,p ₀ ,p ₁ , . . . ,p _(N) _(ldpc) _(−K) _(ldpc) ⁻¹]  [Equation 1]

The LDPC code parameters for PLS1 and PLS2 are as following table 4.

TABLE 4 Signaling Kldpc code Type Ksig Kbch Nbch_parity (=Nbch) NldpcNldpc_parity rate Qldpc PLS1 342 1020 60 1080 4320 3240 1/4  36 PLS2<1021 >1020 2100 2160 7200 5040 3/10 56

The LDPC parity puncturing block can perform puncturing on the PLS1 dataand PLS 2 data.

When shortening is applied to the PLS1 data protection, some LDPC paritybits are punctured after LDPC encoding. Also, for the PLS2 dataprotection, the LDPC parity bits of PLS2 are punctured after LDPCencoding. These punctured bits are not transmitted.

The bit interleaver 6010 can interleave the each shortened and puncturedPLS1 data and PLS2 data.

The constellation mapper 6020 can map the bit interleaved PLS1 data andPLS2 data onto constellations.

The above-described blocks may be omitted or replaced by blocks havingsimilar or identical functions.

FIG. 6 illustrates a frame building block according to one embodiment ofthe present invention.

The frame building block illustrated in FIG. 6 corresponds to anembodiment of the frame building block 1020 described with reference toFIG. 1.

Referring to FIG. 6, the frame building block can include a delaycompensation block 7000, a cell mapper 7010 and a frequency interleaver7020. Description will be given of each block of the frame buildingblock.

The delay compensation block 7000 can adjust the timing between the datapipes and the corresponding PLS data to ensure that they are co-timed atthe transmitter end. The PLS data is delayed by the same amount as datapipes are by addressing the delays of data pipes caused by the InputFormatting block and BICM block. The delay of the BICM block is mainlydue to the time interleaver 5050. In-band signaling data carriesinformation of the next TI group so that they are carried one frameahead of the DPs to be signaled. The Delay Compensating block delaysin-band signaling data accordingly.

The cell mapper 7010 can map PLS, EAC, FIC, DPs, auxiliary streams anddummy cells into the active carriers of the OFDM symbols in the frame.The basic function of the cell mapper 7010 is to map data cells producedby the TIs for each of the DPs, PLS cells, and EAC/FIC cells, if any,into arrays of active OFDM cells corresponding to each of the OFDMsymbols within a frame. Service signaling data (such as PSI (programspecific information)/SI) can be separately gathered and sent by a datapipe. The Cell Mapper operates according to the dynamic informationproduced by the scheduler and the configuration of the frame structure.Details of the frame will be described later.

The frequency interleaver 7020 can randomly interleave data cellsreceived from the cell mapper 7010 to provide frequency diversity. Also,the frequency interleaver 7020 can operate on very OFDM symbol paircomprised of two sequential OFDM symbols using a differentinterleaving-seed order to get maximum interleaving gain in a singleframe.

The above-described blocks may be omitted or replaced by blocks havingsimilar or identical functions.

FIG. 7 illustrates an OFDM generation block according to an embodimentof the present invention.

The OFDM generation block illustrated in FIG. 7 corresponds to anembodiment of the OFDM generation block 1030 described with reference toFIG. 1.

The OFDM generation block modulates the OFDM carriers by the cellsproduced by the Frame Building block, inserts the pilots, and producesthe time domain signal for transmission. Also, this block subsequentlyinserts guard intervals, and applies PAPR (Peak-to-Average Power Radio)reduction processing to produce the final RF signal.

Referring to FIG. 7, the OFDM generation block can include a pilot andreserved tone insertion block 8000, a 2D-eSFN encoding block 8010, anIFFT (Inverse Fast Fourier Transform) block 8020, a PAPR reduction block8030, a guard interval insertion block 8040, a preamble insertion block8050, other system insertion block 8060 and a DAC block 8070.

The other system insertion block 8060 can multiplex signals of aplurality of broadcast transmission/reception systems in the time domainsuch that data of two or more different broadcast transmission/receptionsystems providing broadcast services can be simultaneously transmittedin the same RF signal bandwidth. In this case, the two or more differentbroadcast transmission/reception systems refer to systems providingdifferent broadcast services. The different broadcast services may referto a terrestrial broadcast service, mobile broadcast service, etc.

FIG. 8 illustrates a structure of an apparatus for receiving broadcastsignals for future broadcast services according to an embodiment of thepresent invention.

The apparatus for receiving broadcast signals for future broadcastservices according to an embodiment of the present invention cancorrespond to the apparatus for transmitting broadcast signals forfuture broadcast services, described with reference to FIG. 1.

The apparatus for receiving broadcast signals for future broadcastservices according to an embodiment of the present invention can includea synchronization & demodulation module 9000, a frame parsing module9010, a demapping & decoding module 9020, an output processor 9030 and asignaling decoding module 9040. A description will be given of operationof each module of the apparatus for receiving broadcast signals.

The synchronization & demodulation module 9000 can receive input signalsthrough m Rx antennas, perform signal detection and synchronization withrespect to a system corresponding to the apparatus for receivingbroadcast signals and carry out demodulation corresponding to a reverseprocedure of the procedure performed by the apparatus for transmittingbroadcast signals.

The frame parsing module 9010 can parse input signal frames and extractdata through which a service selected by a user is transmitted. If theapparatus for transmitting broadcast signals performs interleaving, theframe parsing module 9010 can carry out deinterleaving corresponding toa reverse procedure of interleaving. In this case, the positions of asignal and data that need to be extracted can be obtained by decodingdata output from the signaling decoding module 9040 to restorescheduling information generated by the apparatus for transmittingbroadcast signals.

The demapping & decoding module 9020 can convert the input signals intobit domain data and then deinterleave the same as necessary. Thedemapping & decoding module 9020 can perform demapping for mappingapplied for transmission efficiency and correct an error generated on atransmission channel through decoding. In this case, the demapping &decoding module 9020 can obtain transmission parameters necessary fordemapping and decoding by decoding the data output from the signalingdecoding module 9040.

The output processor 9030 can perform reverse procedures of variouscompression/signal processing procedures which are applied by theapparatus for transmitting broadcast signals to improve transmissionefficiency. In this case, the output processor 9030 can acquirenecessary control information from data output from the signalingdecoding module 9040. The output of the output processor 8300corresponds to a signal input to the apparatus for transmittingbroadcast signals and may be MPEG-TSs, IP streams (v4 or v6) and genericstreams.

The signaling decoding module 9040 can obtain PLS information from thesignal demodulated by the synchronization & demodulation module 9000. Asdescribed above, the frame parsing module 9010, demapping & decodingmodule 9020 and output processor 9030 can execute functions thereofusing the data output from the signaling decoding module 9040.

FIG. 9 illustrates a frame structure according to an embodiment of thepresent invention.

FIG. 9 shows an example configuration of the frame types and FRUs in asuper-frame. (a) shows a super frame according to an embodiment of thepresent invention, (b) shows FRU (Frame Repetition Unit) according to anembodiment of the present invention, (c) shows frames of variable PHYprofiles in the FRU and (d) shows a structure of a frame.

A super-frame may be composed of eight FRUs. The FRU is a basicmultiplexing unit for TDM of the frames, and is repeated eight times ina super-frame.

Each frame in the FRU belongs to one of the PHY profiles, (base,handheld, advanced) or FEF. The maximum allowed number of the frames inthe FRU is four and a given PHY profile can appear any number of timesfrom zero times to four times in the FRU (e.g., base, base, handheld,advanced). PHY profile definitions can be extended using reserved valuesof the PHY_PROFILE in the preamble, if required.

The FEF part is inserted at the end of the FRU, if included. When theFEF is included in the FRU, the minimum number of FEFs is 8 in asuper-frame. It is not recommended that FEF parts be adjacent to eachother.

One frame is further divided into a number of OFDM symbols and apreamble. As shown in (d), the frame comprises a preamble, one or moreframe signaling symbols (FSS), normal data symbols and a frame edgesymbol (FES).

The preamble is a special symbol that enables fast Futurecast UTB systemsignal detection and provides a set of basic transmission parameters forefficient transmission and reception of the signal. The detaileddescription of the preamble will be will be described later.

The main purpose of the FSS(s) is to carry the PLS data. For fastsynchronization and channel estimation, and hence fast decoding of PLSdata, the FSS has more dense pilot pattern than the normal data symbol.The FES has exactly the same pilots as the FSS, which enablesfrequency-only interpolation within the FES and temporal interpolation,without extrapolation, for symbols immediately preceding the FES.

FIG. 10 illustrates a signaling hierarchy structure of the frameaccording to an embodiment of the present invention.

FIG. 10 illustrates the signaling hierarchy structure, which is splitinto three main parts: the preamble signaling data 11000, the PLS1 data11010 and the PLS2 data 11020. The purpose of the preamble, which iscarried by the preamble symbol in every frame, is to indicate thetransmission type and basic transmission parameters of that frame. ThePLS1 enables the receiver to access and decode the PLS2 data, whichcontains the parameters to access the DP of interest. The PLS2 iscarried in every frame and split into two main parts: PLS2-STAT data andPLS2-DYN data. The static and dynamic portion of PLS2 data is followedby padding, if necessary.

FIG. 11 illustrates preamble signaling data according to an embodimentof the present invention.

Preamble signaling data carries 21 bits of information that are neededto enable the receiver to access PLS data and trace DPs within the framestructure. Details of the preamble signaling data are as follows:

PHY_PROFILE: This 3-bit field indicates the PHY profile type of thecurrent frame. The mapping of different PHY profile types is given inbelow table 5.

TABLE 5 Value PHY profile 000 Base profile 001 Handheld profile 010Advanced profiled 011~110 Reserved 111 FEF

FFT_SIZE: This 2 bit field indicates the FFT size of the current framewithin a frame-group, as described in below table 6.

TABLE 6 Value FFT size 00  8K FFT 01 16K FFT 10 32K FFT 11 Reserved

GI_FRACTION: This 3 bit field indicates the guard interval fractionvalue in the current super-frame, as described in below table 7.

TABLE 7 Value GI_FRACTION 000 ⅕ 001 1/10 010 1/20 011 1/40 100 1/80 1011/160 110~111 Reserved

EAC_FLAG: This 1 bit field indicates whether the EAC is provided in thecurrent frame. If this field is set to ‘1’, emergency alert service(EAS) is provided in the current frame. If this field set to ‘0’, EAS isnot carried in the current frame. This field can be switched dynamicallywithin a super-frame.

PILOT_MODE: This 1-bit field indicates whether the pilot mode is mobilemode or fixed mode for the current frame in the current frame-group. Ifthis field is set to ‘0’, mobile pilot mode is used. If the field is setto 1′, the fixed pilot mode is used.

PAPR_FLAG: This 1-bit field indicates whether PAPR reduction is used forthe current frame in the current frame-group. If this field is set tovalue ‘1’, tone reservation is used for PAPR reduction. If this field isset to ‘0’, PAPR reduction is not used.

FRU_CONFIGURE: This 3-bit field indicates the PHY profile typeconfigurations of the frame repetition units (FRU) that are present inthe current super-frame. All profile types conveyed in the currentsuper-frame are identified in this field in all preambles in the currentsuper-frame. The 3-bit field has a different definition for eachprofile, as show in below table 8.

TABLE 8 Current Current Current PHY_PROFILE = PHY_PROFILE = CurrentPHY_PROFILE = ‘001’ ‘010’ PHY_PROFILE = ‘000’ (base) (handheld)(advanced) ‘111’ (FEF) FRU_CONFIGURE = Only base Only handheld Onlyadvanced Only FEF 000 profile present profile present profile presentpresent FRU_CONFIGURE = Handheld Base profile Base profile Base profile1XX profile present present present present FRU_CONFIGURE = AdvancedAdvanced Handheld Handheld X1X profile profile profile profile presentpresent present present FRU_CONFIGURE = FEF FEF FEF Advanced XX1 presentpresent present profile present

RESERVED: This 7-bit field is reserved for future use.

FIG. 12 illustrates PLS1 data according to an embodiment of the presentinvention.

PLS1 data provides basic transmission parameters including parametersrequired to enable the reception and decoding of the PLS2. As abovementioned, the PLS1 data remain unchanged for the entire duration of oneframe-group. The detailed definition of the signaling fields of the PLS1data are as follows:

PREAMBLE_DATA: This 20-bit field is a copy of the preamble signalingdata excluding the EAC_FLAG.

NUM_FRAME_FRU: This 2-bit field indicates the number of the frames perFRU.

PAYLOAD_TYPE: This 3-bit field indicates the format of the payload datacarried in the frame-group. PAYLOAD_TYPE is signaled as shown in table9.

TABLE 9 value Payload type 1XX TS stream is transmitted X1X IP stream istransmitted XX1 GS stream is transmitted

NUM_FSS: This 2-bit field indicates the number of FSS symbols in thecurrent frame.

SYSTEM_VERSION: This 8-bit field indicates the version of thetransmitted signal format. The SYSTEM_VERSION is divided into two 4-bitfields, which are a major version and a minor version.

Major version: The MSB four bits of SYSTEM_VERSION field indicate majorversion information. A change in the major version field indicates anon-backward-compatible change. The default value is ‘0000’. For theversion described in this standard, the value is set to ‘0000’.

Minor version: The LSB four bits of SYSTEM_VERSION field indicate minorversion information. A change in the minor version field isbackward-compatible.

CELL_ID: This is a 16-bit field which uniquely identifies a geographiccell in an ATSC network. An ATSC cell coverage area may consist of oneor more frequencies, depending on the number of frequencies used perFuturecast UTB system. If the value of the CELL_ID is not known orunspecified, this field is set to ‘0’.

NETWORK_ID: This is a 16-bit field which uniquely identifies the currentATSC network.

SYSTEM_ID: This 16-bit field uniquely identifies the Futurecast UTBsystem within the ATSC network. The Futurecast UTB system is theterrestrial broadcast system whose input is one or more input streams(TS, IP, GS) and whose output is an RF signal. The Futurecast UTB systemcarries one or more PHY profiles and FEF, if any. The same FuturecastUTB system may carry different input streams and use different RFfrequencies in different geographical areas, allowing local serviceinsertion. The frame structure and scheduling is controlled in one placeand is identical for all transmissions within a Futurecast UTB system.One or more Futurecast UTB systems may have the same SYSTEM_ID meaningthat they all have the same physical layer structure and configuration.

The following loop consists of FRU_PHY_PROFILE, FRU_FRAME_LENGTH,FRU_GI_FRACTION, and RESERVED which are used to indicate the FRUconfiguration and the length of each frame type. The loop size is fixedso that four PHY profiles (including a FEF) are signaled within the FRU.If NUM_FRAME_FRU is less than 4, the unused fields are filled withzeros.

FRU_PHY_PROFILE: This 3-bit field indicates the PHY profile type of the(i+1)th (i is the loop index) frame of the associated FRU. This fielduses the same signaling format as shown in the table 8.

FRU_FRAME_LENGTH: This 2-bit field indicates the length of the (i+1)thframe of the associated FRU. Using FRU_FRAME_LENGTH together withFRU_GI_FRACTION, the exact value of the frame duration can be obtained.

FRU_GI_FRACTION: This 3-bit field indicates the guard interval fractionvalue of the (i+1)th frame of the associated FRU. FRU_GI_FRACTION issignaled according to the table 7.

RESERVED: This 4-bit field is reserved for future use.

The following fields provide parameters for decoding the PLS2 data.

PLS2_FEC_TYPE: This 2-bit field indicates the FEC type used by the PLS2protection. The FEC type is signaled according to table 10. The detailsof the LDPC codes will be described later.

TABLE 10 Content PLS2 FEC type 00 4K-1/4 and 7K-3/10 LDPC codes 01~11Reserved

PLS2_MOD: This 3-bit field indicates the modulation type used by thePLS2. The modulation type is signaled according to table 11.

TABLE 11 Value PLS2_MODE 000 BPSK 001 QPSK 010 QAM-16 011 NUQ-64 100~111Reserved

PLS2_SIZE_CELL: This 15-bit field indicates Ctotal_partial_block, thesize (specified as the number of QAM cells) of the collection of fullcoded blocks for PLS2 that is carried in the current frame-group. Thisvalue is constant during the entire duration of the current frame-group.

PLS2_STAT_SIZE_BIT: This 14-bit field indicates the size, in bits, ofthe PLS2-STAT for the current frame-group. This value is constant duringthe entire duration of the current frame-group.

PLS2_DYN_SIZE_BIT: This 14-bit field indicates the size, in bits, of thePLS2-DYN for the current frame-group. This value is constant during theentire duration of the current frame-group.

PLS2_REP_FLAG: This 1-bit flag indicates whether the PLS2 repetitionmode is used in the current frame-group. When this field is set to value‘1’, the PLS2 repetition mode is activated. When this field is set tovalue ‘0’, the PLS2 repetition mode is deactivated.

PLS2_REP_SIZE_CELL: This 15-bit field indicates Ctotal_partial_block,the size (specified as the number of QAM cells) of the collection ofpartial coded blocks for PLS2 carried in every frame of the currentframe-group, when PLS2 repetition is used. If repetition is not used,the value of this field is equal to 0. This value is constant during theentire duration of the current frame-group.

PLS2 NEXT_FEC_TYPE: This 2-bit field indicates the FEC type used forPLS2 that is carried in every frame of the next frame-group. The FECtype is signaled according to the table 10.

PLS2_NEXT_MOD: This 3-bit field indicates the modulation type used forPLS2 that is carried in every frame of the next frame-group. Themodulation type is signaled according to the table 11.

PLS2 NEXT_REP_FLAG: This 1-bit flag indicates whether the PLS2repetition mode is used in the next frame-group. When this field is setto value ‘1’, the PLS2 repetition mode is activated. When this field isset to value ‘0’, the PLS2 repetition mode is deactivated.

PLS2_NEXT_REP_SIZE_CELL: This 15-bit field indicates Ctotal_full_block,The size (specified as the number of QAM cells) of the collection offull coded blocks for PLS2 that is carried in every frame of the nextframe-group, when PLS2 repetition is used. If repetition is not used inthe next frame-group, the value of this field is equal to 0. This valueis constant during the entire duration of the current frame-group.

PLS2 NEXT_REP_STAT_SIZE_BIT: This 14-bit field indicates the size, inbits, of the PLS2-STAT for the next frame-group. This value is constantin the current frame-group.

PLS2NEXT_REP_DYN_SIZE_BIT: This 14-bit field indicates the size, inbits, of the PLS2-DYN for the next frame-group. This value is constantin the current frame-group.

PLS2_AP_MODE: This 2-bit field indicates whether additional parity isprovided for PLS2 in the current frame-group. This value is constantduring the entire duration of the current frame-group. The below table12 gives the values of this field. When this field is set to ‘00’,additional parity is not used for the PLS2 in the current frame-group.

TABLE 12 Value PLS2-AP mode 00 AP is not provided 01 AP1 mode 10~11Reserved

PLS2_AP_SIZE_CELL: This 15-bit field indicates the size (specified asthe number of QAM cells) of the additional parity bits of the PLS2. Thisvalue is constant during the entire duration of the current frame-group.

PLS2_NEXT_AP_MODE: This 2-bit field indicates whether additional parityis provided for PLS2 signaling in every frame of next frame-group. Thisvalue is constant during the entire duration of the current frame-group.The table 12 defines the values of this field

PLS2_NEXT_AP_SIZE_CELL: This 15-bit field indicates the size (specifiedas the number of QAM cells) of the additional parity bits of the PLS2 inevery frame of the next frame-group. This value is constant during theentire duration of the current frame-group.

RESERVED: This 32-bit field is reserved for future use.

CRC_32: A 32-bit error detection code, which is applied to the entirePLS1 signaling.

FIG. 13 illustrates PLS2 data according to an embodiment of the presentinvention.

FIG. 13 illustrates PLS2-STAT data of the PLS2 data. The PLS2-STAT dataare the same within a frame-group, while the PLS2-DYN data provideinformation that is specific for the current frame.

The details of fields of the PLS2-STAT data are as follows:

FIC_FLAG: This 1-bit field indicates whether the FIC is used in thecurrent frame-group. If this field is set to ‘1’, the FIC is provided inthe current frame. If this field set to ‘0’, the FIC is not carried inthe current frame. This value is constant during the entire duration ofthe current frame-group.

AUX_FLAG: This 1-bit field indicates whether the auxiliary stream(s) isused in the current frame-group. If this field is set to ‘1’, theauxiliary stream is provided in the current frame. If this field set to‘0’, the auxiliary stream is not carried in the current frame. Thisvalue is constant during the entire duration of current frame-group.

NUM_DP: This 6-bit field indicates the number of DPs carried within thecurrent frame. The value of this field ranges from 1 to 64, and thenumber of DPs is NUM_DP+1.

DP_ID: This 6-bit field identifies uniquely a DP within a PHY profile.

DP_TYPE: This 3-bit field indicates the type of the DP. This is signaledaccording to the below table 13.

TABLE 13 Value DP Type 000 DP Type 1 001 DP Type 2 010~111 reserved

DP_GROUP_ID: This 8-bit field identifies the DP group with which thecurrent DP is associated. This can be used by a receiver to access theDPs of the service components associated with a particular service,which will have the same DP_GROUP_ID.

BASE_DP_ID: This 6-bit field indicates the DP carrying service signalingdata (such as PSI/SI) used in the Management layer. The DP indicated byBASE_DP_ID may be either a normal DP carrying the service signaling dataalong with the service data or a dedicated DP carrying only the servicesignaling data

DP_FEC_TYPE: This 2-bit field indicates the FEC type used by theassociated DP. The FEC type is signaled according to the below table 14.

TABLE 14 Value FEC_TYPE 00 16K LDPC 01 64K LDPC 10~11 Reserved

DP_COD: This 4-bit field indicates the code rate used by the associatedDP. The code rate is signaled according to the below table 15.

TABLE 15 Value Code rate 0000 5/15 0001 6/15 0010 7/15 0011 8/15 01009/15 0101 10/15  0110 11/15  0111 12/15  1000 13/15  1001~1111 Reserved

DP_MOD: This 4-bit field indicates the modulation used by the associatedDP. The modulation is signaled according to the below table 16.

TABLE 16 Value Modulation 0000 QPSK 0001 QAM-16 0010 NUQ-64 0011 NUQ-2560100 NUQ-1024 0101 NUC-16 0110 NUC-64 0111 NUC-256 1000 NUC-10241001~1111 reserved

DP_SSD_FLAG: This 1-bit field indicates whether the SSD mode is used inthe associated DP. If this field is set to value ‘1’, SSD is used. Ifthis field is set to value ‘0’, SSD is not used.

The following field appears only if PHY_PROFILE is equal to ‘010’, whichindicates the advanced profile:

DP_MIMO: This 3-bit field indicates which type of MIMO encoding processis applied to the associated DP. The type of MIMO encoding process issignaled according to the table 17.

TABLE 17 Value MIMO encoding 000 FR-SM 001 FRFD-SM 010~111 reserved

DP_TI_TYPE: This 1-bit field indicates the type of time-interleaving. Avalue of ‘0’ indicates that one TI group corresponds to one frame andcontains one or more TI-blocks. A value of ‘1’ indicates that one TIgroup is carried in more than one frame and contains only one TI-block.

DP_TI_LENGTH: The use of this 2-bit field (the allowed values are only1, 2, 4, 8) is determined by the values set within the DP_TI_TYPE fieldas follows:

If the DP_TI_TYPE is set to the value ‘1’, this field indicates PI, thenumber of the frames to which each TI group is mapped, and there is oneTI-block per TI group (NTI=1). The allowed PI values with 2-bit fieldare defined in the below table 18.

If the DP_TI_TYPE is set to the value ‘0’, this field indicates thenumber of TI-blocks NTI per TI group, and there is one TI group perframe (PI=1). The allowed PI values with 2-bit field are defined in thebelow table 18.

TABLE 18 2-bit field PI NTI 00 1 1 01 2 2 10 4 3 11 8 4

DP_FRAME_INTERVAL: This 2-bit field indicates the frame interval (IJUMP)within the frame-group for the associated DP and the allowed values are1, 2, 4, 8 (the corresponding 2-bit field is ‘00’, ‘01’, ‘10’, or ‘11’,respectively). For DPs that do not appear every frame of theframe-group, the value of this field is equal to the interval betweensuccessive frames. For example, if a DP appears on the frames 1, 5, 9,13, etc., this field is set to ‘4’. For DPs that appear in every frame,this field is set to ‘1’.

DP_TI_BYPASS: This 1-bit field determines the availability of timeinterleaver 5050. If time interleaving is not used for a DP, it is setto ‘1’. Whereas if time interleaving is used it is set to ‘0’.

DP_FIRST_FRAME_IDX: This 5-bit field indicates the index of the firstframe of the super-frame in which the current DP occurs. The value ofDP_FIRST_FRAME_IDX ranges from 0 to 31

DP_NUM_BLOCK_MAX: This 10-bit field indicates the maximum value ofDP_NUM_BLOCKS for this DP. The value of this field has the same range asDP_NUM_BLOCKS.

DP_PAYLOAD_TYPE: This 2-bit field indicates the type of the payload datacarried by the given DP. DP_PAYLOAD_TYPE is signaled according to thebelow table 19.

TABLE 19 Value Payload Type 00 TS. 01 IP 10 GS 11 reserved

DP_INBAND_MODE: This 2-bit field indicates whether the current DPcarries in-band signaling information. The in-band signaling type issignaled according to the below table 20.

TABLE 20 Value In-band mode 00 In-band signaling is not carried. 01INBAND-PLS is carried only 10 INBAND-ISSY is carried only 11 INBAND-PLSand INBAND-ISSY are carried

DP_PROTOCOL_TYPE: This 2-bit field indicates the protocol type of thepayload carried by the given DP. It is signaled according to the belowtable 21 when input payload types are selected.

TABLE 21 If DP_PAY- If DP_PAY- If DP_PAY- LOAD_TYPE LOAD_TYPE LOAD_TYPEValue Is TS Is IP Is GS 00 MPEG2-TS IPv4 (Note) 01 Reserved IPv6Reserved 10 Reserved Reserved Reserved 11 Reserved Reserved Reserved

DP_CRC_MODE: This 2-bit field indicates whether CRC encoding is used inthe Input Formatting block. The CRC mode is signaled according to thebelow table 22.

TABLE 22 Value CRC mode 00 Not used 01 CRC-8 10 CRC-16 11 CRC-32

DNP_MODE: This 2-bit field indicates the null-packet deletion mode usedby the associated DP when DP_PAYLOAD_TYPE is set to TS (‘00’). DNP_MODEis signaled according to the below table 23. If DP_PAYLOAD_TYPE is notTS (‘00’), DNP_MODE is set to the value ‘00’.

TABLE 23 Value Null-packet deletion mode 00 Not used 01 DNP-NORMAL 10DNP-OFFSET 11 reserved

ISSY_MODE: This 2-bit field indicates the ISSY mode used by theassociated DP when DP_PAYLOAD_TYPE is set to TS (‘00’). The ISSY_MODE issignaled according to the below table 24 If DP_PAYLOAD_TYPE is not TS(‘00’), ISSY_MODE is set to the value ‘00’.

TABLE 24 Value ISSY mode 00 Not used 01 ISSY-UP 10 ISSY-BBF 11 reserved

HC_MODE_TS: This 2-bit field indicates the TS header compression modeused by the associated DP when DP_PAYLOAD_TYPE is set to TS (‘00’). TheHC_MODE_TS is signaled according to the below table 25.

TABLE 25 Value Header compression mode 00 HC_MODE_TS 1 01 HC_MODE_TS 210 HC_MODE_TS 3 11 HC_MODE_TS 4

HC_MODE_IP: This 2-bit field indicates the IP header compression modewhen DP_PAYLOAD_TYPE is set to IP (‘01’). The HC_MODE_IP is signaledaccording to the below table 26.

TABLE 26 Value Header compression mode 00 No compression 01 HC_MODE_IP 110~11 reserved

PID: This 13-bit field indicates the PID number for TS headercompression when DP_PAYLOAD_TYPE is set to TS (‘00’) and HC_MODE_TS isset to ‘01’ or ‘10’.

RESERVED: This 8-bit field is reserved for future use.

The following field appears only if FIC_FLAG is equal to ‘1’:

FIC_VERSION: This 8-bit field indicates the version number of the FIC.

FIC_LENGTH_BYTE: This 13-bit field indicates the length, in bytes, ofthe FIC.

RESERVED: This 8-bit field is reserved for future use.

The following field appears only if AUX_FLAG is equal to ‘1’:

NUM_AUX: This 4-bit field indicates the number of auxiliary streams.Zero means no auxiliary streams are used.

AUX_CONFIG_RFU: This 8-bit field is reserved for future use.

AUX_STREAM_TYPE: This 4-bit is reserved for future use for indicatingthe type of the current auxiliary stream.

AUX_PRIVATE_CONFIG: This 28-bit field is reserved for future use forsignaling auxiliary streams.

FIG. 14 illustrates PLS2 data according to another embodiment of thepresent invention.

FIG. 14 illustrates PLS2-DYN data of the PLS2 data. The values of thePLS2-DYN data may change during the duration of one frame-group, whilethe size of fields remains constant.

The details of fields of the PLS2-DYN data are as follows:

FRAME_INDEX: This 5-bit field indicates the frame index of the currentframe within the super-frame. The index of the first frame of thesuper-frame is set to ‘0’.

PLS_CHANGE_COUNTER: This 4-bit field indicates the number ofsuper-frames ahead where the configuration will change. The nextsuper-frame with changes in the configuration is indicated by the valuesignaled within this field. If this field is set to the value ‘0000’, itmeans that no scheduled change is foreseen: e.g., value ‘1’ indicatesthat there is a change in the next super-frame.

FIC_CHANGE_COUNTER: This 4-bit field indicates the number ofsuper-frames frames ahead where the configuration (i.e., the contents ofthe FIC) will change. The next super-frame with changes in theconfiguration is indicated by the value signaled within this field. Ifthis field is set to the value ‘0000’, it means that no scheduled changeis foreseen: e.g. value ‘0001’ indicates that there is a change in thenext super-frame.

RESERVED: This 16-bit field is reserved for future use.

The following fields appear in the loop over NUM_DP, which describe theparameters associated with the DP carried in the current frame.

DP_ID: This 6-bit field indicates uniquely the DP within a PHY profile.

DP_START: This 15-bit (or 13-bit) field indicates the start position ofthe first of the DPs using the DPU addressing scheme. The DP_START fieldhas differing length according to the PHY profile and FFT size as shownin the below table 27.

TABLE 27 DP_START field size PHY profile 64K 16K Base 13 bit 15 bitHandheld — 13 bit Advanced 13 bit 15 bit

DP_NUM_BLOCK: This 10-bit field indicates the number of FEC blocks inthe current TI group for the current DP. The value of DP_NUM_BLOCKranges from 0 to 1023

RESERVED: This 8-bit field is reserved for future use.

The following fields indicate the FIC parameters associated with theEAC.

EAC_FLAG: This 1-bit field indicates the existence of the EAC in thecurrent frame. This bit is the same value as the EAC_FLAG in thepreamble.

EAS_WAKE_UP_VERSION_NUM: This 8-bit field indicates the version numberof a wake-up indication.

If the EAC_FLAG field is equal to ‘1’, the following 12 bits areallocated for EAC_LENGTH_BYTE field. If the EAC_FLAG field is equal to‘0’, the following 12 bits are allocated for EAC_COUNTER.

EAC_LENGTH_BYTE: This 12-bit field indicates the length, in byte, of theEAC.

EAC_COUNTER: This 12-bit field indicates the number of the frames beforethe frame where the EAC arrives.

The following field appears only if the AUX_FLAG field is equal to I′:

AUX_PRIVATE_DYN: This 48-bit field is reserved for future use forsignaling auxiliary streams. The meaning of this field depends on thevalue of AUX_STREAM_TYPE in the configurable PLS2-STAT.

CRC_32: A 32-bit error detection code, which is applied to the entirePLS2.

FIG. 15 illustrates a logical structure of a frame according to anembodiment of the present invention.

As above mentioned, the PLS, EAC, FIC, DPs, auxiliary streams and dummycells are mapped into the active carriers of the OFDM symbols in theframe. The PLS1 and PLS2 are first mapped into one or more FSS(s). Afterthat, EAC cells, if any, are mapped immediately following the PLS field,followed next by FIC cells, if any. The DPs are mapped next after thePLS or EAC, FIC, if any. Type 1 DPs follows first, and Type 2 DPs next.The details of a type of the DP will be described later. In some case,DPs may carry some special data for EAS or service signaling data. Theauxiliary stream or streams, if any, follow the DPs, which in turn arefollowed by dummy cells. Mapping them all together in the abovementioned order, i.e. PLS, EAC, FIC, DPs, auxiliary streams and dummydata cells exactly fill the cell capacity in the frame.

FIG. 16 illustrates PLS mapping according to an embodiment of thepresent invention.

PLS cells are mapped to the active carriers of FSS(s). Depending on thenumber of cells occupied by PLS, one or more symbols are designated asFSS(s), and the number of FSS(s) NFSS is signaled by NUM_FSS in PLS1.The FSS is a special symbol for carrying PLS cells. Since robustness andlatency are critical issues in the PLS, the FSS(s) has higher density ofpilots allowing fast synchronization and frequency-only interpolationwithin the FSS.

PLS cells are mapped to active carriers of the NFSS FSS(s) in a top-downmanner as shown in an example in FIG. 16. The PLS1 cells are mappedfirst from the first cell of the first FSS in an increasing order of thecell index. The PLS2 cells follow immediately after the last cell of thePLS1 and mapping continues downward until the last cell index of thefirst FSS. If the total number of required PLS cells exceeds the numberof active carriers of one FSS, mapping proceeds to the next FSS andcontinues in exactly the same manner as the first FSS.

After PLS mapping is completed, DPs are carried next. If EAC, FIC orboth are present in the current frame, they are placed between PLS and“normal” DPs.

FIG. 17 illustrates EAC mapping according to an embodiment of thepresent invention.

EAC is a dedicated channel for carrying EAS messages and links to theDPs for EAS. EAS support is provided but EAC itself may or may not bepresent in every frame. EAC, if any, is mapped immediately after thePLS2 cells. EAC is not preceded by any of the FIC, DPs, auxiliarystreams or dummy cells other than the PLS cells. The procedure ofmapping the EAC cells is exactly the same as that of the PLS.

The EAC cells are mapped from the next cell of the PLS2 in increasingorder of the cell index as shown in the example in FIG. 17. Depending onthe EAS message size, EAC cells may occupy a few symbols, as shown inFIG. 17.

EAC cells follow immediately after the last cell of the PLS2, andmapping continues downward until the last cell index of the last FSS. Ifthe total number of required EAC cells exceeds the number of remainingactive carriers of the last FSS mapping proceeds to the next symbol andcontinues in exactly the same manner as FSS(s). The next symbol formapping in this case is the normal data symbol, which has more activecarriers than a FSS.

After EAC mapping is completed, the FIC is carried next, if any exists.If FIC is not transmitted (as signaled in the PLS2 field), DPs followimmediately after the last cell of the EAC.

FIG. 18 illustrates FIC mapping according to an embodiment of thepresent invention.

shows an example mapping of FIC cell without EAC and (b) shows anexample mapping of FIC cell with EAC.

FIC is a dedicated channel for carrying cross-layer information toenable fast service acquisition and channel scanning. This informationprimarily includes channel binding information between DPs and theservices of each broadcaster. For fast scan, a receiver can decode FICand obtain information such as broadcaster ID, number of services, andBASE_DP_ID. For fast service acquisition, in addition to FIC, base DPcan be decoded using BASE_DP_ID. Other than the content it carries, abase DP is encoded and mapped to a frame in exactly the same way as anormal DP. Therefore, no additional description is required for a baseDP. The FIC data is generated and consumed in the Management Layer. Thecontent of FIC data is as described in the Management Layerspecification.

The FIC data is optional and the use of FIC is signaled by the FIC_FLAGparameter in the static part of the PLS2. If FIC is used, FIC_FLAG isset to ‘1’ and the signaling field for FIC is defined in the static partof PLS2. Signaled in this field are FIC_VERSION, and FIC_LENGTH_BYTE.FIC uses the same modulation, coding and time interleaving parameters asPLS2. FIC shares the same signaling parameters such as PLS2_MOD and PLS2FEC. FIC data, if any, is mapped immediately after PLS2 or EAC if any.FIC is not preceded by any normal DPs, auxiliary streams or dummy cells.The method of mapping FIC cells is exactly the same as that of EAC whichis again the same as PLS.

Without EAC after PLS, FIC cells are mapped from the next cell of thePLS2 in an increasing order of the cell index as shown in an example in(a). Depending on the FIC data size, FIC cells may be mapped over a fewsymbols, as shown in (b).

FIC cells follow immediately after the last cell of the PLS2, andmapping continues downward until the last cell index of the last FSS. Ifthe total number of required FIC cells exceeds the number of remainingactive carriers of the last FSS, mapping proceeds to the next symbol andcontinues in exactly the same manner as FSS(s). The next symbol formapping in this case is the normal data symbol which has more activecarriers than a FSS.

If EAS messages are transmitted in the current frame, EAC precedes FIC,and FIC cells are mapped from the next cell of the EAC in an increasingorder of the cell index as shown in (b).

After FIC mapping is completed, one or more DPs are mapped, followed byauxiliary streams, if any, and dummy cells.

FIG. 19 illustrates an FEC structure according to an embodiment of thepresent invention.

FIG. 19 illustrates an FEC structure according to an embodiment of thepresent invention before bit interleaving. As above mentioned, Data FECencoder may perform the FEC encoding on the input BBF to generateFECBLOCK procedure using outer coding (BCH), and inner coding (LDPC).The illustrated FEC structure corresponds to the FECBLOCK. Also, theFECBLOCK and the FEC structure have same value corresponding to a lengthof LDPC codeword.

The BCH encoding is applied to each BBF (Kbch bits), and then LDPCencoding is applied to BCH-encoded BBF (Kldpc bits=Nbch bits) asillustrated in FIG. 22.

The value of Nldpc is either 64800 bits (long FECBLOCK) or 16200 bits(short FECBLOCK).

The below table 28 and table 29 show FEC encoding parameters for a longFECBLOCK and a short FECBLOCK, respectively.

TABLE 28 BCH error LDPC correction Nbch − Rate Nldpc Kldpc Kbchcapability Kbch 5/15 64800 21600 21408 12 192 6/15 25920 25728 7/1530240 30048 8/15 34560 34368 9/15 38880 38688 10/15  43200 43008 11/15 47520 47328 12/15  51840 51648 13/15  56160 55968

TABLE 29 BCH error LDPC correction Nbch − Rate Nldpc Kldpc Kbchcapability Kbch 5/15 16200 5400 5232 12 168 6/15 6480 6312 7/15 75607392 8/15 8640 8472 9/15 9720 9552 10/15  10800 10632 11/15  11880 1171212/15  12960 12792 13/15  14040 13872

The details of operations of the BCH encoding and LDPC encoding are asfollows:

A 12-error correcting BCH code is used for outer encoding of the BBF.The BCH generator polynomial for short FECBLOCK and long FECBLOCK areobtained by multiplying together all polynomials.

LDPC code is used to encode the output of the outer BCH encoding. Togenerate a completed Bldpc (FECBLOCK), Pldpc (parity bits) is encodedsystematically from each Ildpc (BCH-encoded BBF), and appended to Ildpc.The completed Bldpc (FECBLOCK) are expressed as follow equation.

B _(ldpc) =[I _(ldpc) P _(ldpc) ]=[i ₀ ,i ₁ , . . . ,i _(K) _(ldpc) ⁻¹,p ₀ ,p ₁ , . . . ,p _(N) _(ldpc) _(−K) _(ldpc) ⁻¹]  [Equation2]

The parameters for long FECBLOCK and short FECBLOCK are given in theabove table 28 and 29, respectively.

The detailed procedure to calculate Nldpc−Kldpc parity bits for longFECBLOCK, is as follows:

1) Initialize the parity bits,

p ₀ =p ₁ =p ₂ = . . . =p _(N) _(ldpc) _(−K) _(ldpc) ⁻¹=0  [Equation3]

2) Accumulate the first information bit—i0, at parity bit addressesspecified in the first row of an addresses of parity check matrix. Thedetails of addresses of parity check matrix will be described later. Forexample, for rate 13/15:

p ₉₈₃ =p ₉₈₃ ⊕i ₀ p ₂₈₁₅ =p ₂₈₁₅ ⊕i ₀

p ₄₈₃₇ =p ₄₈₃₇ ⊕i ₀ p ₄₉₈₉ =p ₄₉₈₉ ⊕i ₀

p ₆₁₃₈ =p ₆₁₃₈ ⊕i ₀ p ₆₄₅₈ =p ₆₄₅₈ ⊕i ₀

p ₆₉₂₁ =p ₆₉₂₁ ⊕i ₀ p ₆₉₇₄ =p ₆₉₇₄ ⊕i ₀

p ₇₅₇₂ =p ₇₅₇₂ ⊕i ₀ p ₈₂₆₀ =p ₈₂₆₀ ⊕i ₀

p ₈₄₉₆ =p ₈₄₉₆ ⊕i ₀  [Equation 4]

3) For the next 359 information bits, is, s=1, 2, . . . , 359 accumulateis at parity bit addresses using following equation.

{x+(S mod 360)×Q _(ldpc)} mod(N _(ldpc) −K _(ldpc))  [Equation 5]

where x denotes the address of the parity bit accumulator correspondingto the first bit i0, and Qldpc is a code rate dependent constantspecified in the addresses of parity check matrix. Continuing with theexample, Qldpc=24 for rate 13/15, so for information bit i1, thefollowing operations are performed:

p ₁₀₀₇ =p ₁₀₀₇ ⊕i ₀ p ₂₈₃₉ =p ₂₈₃₉ ⊕i ₁

p ₄₈₆₁ =p ₄₈₆₁ ⊕i ₁ p ₅₀₁₃ =p ₅₀₁₃ ⊕i ₁

p ₆₁₆₂ =p ₆₁₆₂ ⊕i ₁ p ₆₄₈₂ =p ₆₄₈₂ ⊕i ₁

p ₆₉₄₅ =p ₆₉₄₅ ⊕i ₁ p ₆₉₉₈ =p ₆₉₉₈ ⊕i ₁

p ₇₅₉₆ =p ₇₅₉₆ ⊕i ₁ p ₈₂₈₄ =p ₈₂₈₄ ⊕i ₁

p ₈₅₂₀ =p ₈₅₂₀ ⊕i ₁  [Equation 6]

4) For the 361st information bit i360, the addresses of the parity bitaccumulators are given in the second row of the addresses of paritycheck matrix. In a similar manner the addresses of the parity bitaccumulators for the following 359 information bits is, s=361, 362, . .. , 719 are obtained using the equation 6, where x denotes the addressof the parity bit accumulator corresponding to the information bit i360,i.e., the entries in the second row of the addresses of parity checkmatrix.

5) In a similar manner, for every group of 360 new information bits, anew row from addresses of parity check matrixes used to find theaddresses of the parity bit accumulators.

After all of the information bits are exhausted, the final parity bitsare obtained as follows:

6) Sequentially perform the following operations starting with i=1

p _(i) =p _(i) ⊕p _(i-1) ,i=1,2, . . . ,N _(ldpc) −K_(ldpc)−1  [Equation 7]

where final content of pi, i=0, 1, . . . Nldpc−Kldpc−1 is equal to theparity bit pi.

TABLE 30 Code Rate Qldpc 5/15 120 6/15 108 7/15 96 8/15 84 9/15 7210/15  60 11/15  48 12/15  36 13/15  24

This LDPC encoding procedure for a short FECBLOCK is in accordance withthe LDPC encoding procedure for the long FECBLOCK, except replacing thetable 30 with table 31, and replacing the addresses of parity checkmatrix for the long FECBLOCK with the addresses of parity check matrixfor the short FECBLOCK.

TABLE 31 Code Rate Qldpc 5/15 30 6/15 27 7/15 24 8/15 21 9/15 18 10/15 15 11/15  12 12/15  9 13/15  6

FIG. 20 illustrates a time interleaving according to an embodiment ofthe present invention.

(a) to (c) show examples of TI mode.

The time interleaver operates at the DP level. The parameters of timeinterleaving (TI) may be set differently for each DP.

The following parameters, which appear in part of the PLS2-STAT data,configure the TI:

DP_TI_TYPE (allowed values: 0 or 1): Represents the TI mode; ‘0’indicates the mode with multiple TI blocks (more than one TI block) perTI group. In this case, one TI group is directly mapped to one frame (nointer-frame interleaving). ‘1’ indicates the mode with only one TI blockper TI group. In this case, the TI block may be spread over more thanone frame (inter-frame interleaving).

DP_TI_LENGTH: If DP_TI_TYPE=‘0’, this parameter is the number of TIblocks NTI per TI group. For DP_TI_TYPE=1′, this parameter is the numberof frames PI spread from one TI group.

DP_NUM_BLOCK_MAX (allowed values: 0 to 1023): Represents the maximumnumber of XFECBLOCKs per TI group.

DP_FRAME_INTERVAL (allowed values: 1, 2, 4, 8): Represents the number ofthe frames HUMP between two successive frames carrying the same DP of agiven PHY profile.

DP_TI_BYPASS (allowed values: 0 or 1): If time interleaving is not usedfor a DP, this parameter is set to ‘1’. It is set to ‘0’ if timeinterleaving is used.

Additionally, the parameter DP_NUM_BLOCK from the PLS2-DYN data is usedto represent the number of XFECBLOCKs carried by one TI group of the DP.

When time interleaving is not used for a DP, the following TI group,time interleaving operation, and TI mode are not considered. However,the Delay Compensation block for the dynamic configuration informationfrom the scheduler will still be required. In each DP, the XFECBLOCKsreceived from the SSD/MIMO encoding are grouped into TI groups. That is,each TI group is a set of an integer number of XFECBLOCKs and willcontain a dynamically variable number of XFECBLOCKs. The number ofXFECBLOCKs in the TI group of index n is denoted by NxBLOCK_Group(n) andis signaled as DP_NUM_BLOCK in the PLS2-DYN data. Note thatNxBLOCK_Group(n) may vary from the minimum value of 0 to the maximumvalue NxBLOCK_Group_MAX (corresponding to DP_NUM_BLOCK_MAX) of which thelargest value is 1023.

Each TI group is either mapped directly onto one frame or spread over PIframes. Each TI group is also divided into more than one TI blocks(NTI), where each TI block corresponds to one usage of time interleavermemory. The TI blocks within the TI group may contain slightly differentnumbers of XFECBLOCKs. If the TI group is divided into multiple TIblocks, it is directly mapped to only one frame. There are three optionsfor time interleaving (except the extra option of skipping the timeinterleaving) as shown in the below table 32.

TABLE 32 Modes Descriptions Option-1 Each TI group contains one TI blockand is mapped directly to one frame as shown in (a). This option issignaled in the PLS2-STAT by DP_TI_TYPE = ‘0’ and DP_TI_LENGTH = ‘1’(NTI= 1). Option-2 Each TI group contains one TI block and is mapped to morethan one frame. (b) shows an example, where one TI group is mapped totwo frames, i.e., DP_TI_LENGTH = ‘2’ (PI = 2) and DP_FRAME_INTERVAL(IJUMP = 2). This provides greater time diversity for low data-rateservices. This option is signaled in the PLS2-STAT by DP_TI_TYPE = ‘1’.Option-3 Each TI group is divided into multiple TI blocks and is mappeddirectly to one frame as shown in (c). Each TI block may use full TImemory, so as to provide the maximum bit-rate for a DP. This option issignaled in the PLS2-STAT signaling by DP_TI_TYPE = ‘0’ and DP_TI_LENGTH= NTI, while PI = 1.

Typically, the time interleaver will also act as a buffer for DP dataprior to the process of frame building. This is achieved by means of twomemory banks for each DP. The first TI-block is written to the firstbank. The second TI-block is written to the second bank while the firstbank is being read from and so on.

The TI is a twisted row-column block interleaver. For the sth TI blockof the nth TI group, the number of rows N_(r) of a TI memory is equal tothe number of cells N_(cells), i.e., N_(r)=N_(cells) while the number ofcolumns N_(c) is equal to the number N_(xBLOCK) _(_) _(TI)(n,s)

FIG. 21 illustrates the basic operation of a twisted row-column blockinterleaver according to an embodiment of the present invention.

FIG. 21 (a) shows a writing operation in the time interleaver and FIG.21(b) shows a reading operation in the time interleaver The firstXFECBLOCK is written column-wise into the first column of the TI memory,and the second XFECBLOCK is written into the next column, and so on asshown in (a). Then, in the interleaving array, cells are read outdiagonal-wise. During diagonal-wise reading from the first row(rightwards along the row beginning with the left-most column) to thelast row, N_(r) cells are read out as shown in (b). In detail, assumingz_(n,s,i) (i=0, . . . , N_(r)N_(c)) as the TI memory cell position to beread sequentially, the reading process in such an interleaving array isperformed by calculating the row index R_(n,s,i), the column indexC_(n,s,i), and the associated twisting parameter T_(n,s,i) as followsequation.

$\begin{matrix}\begin{matrix}{{{GENERATE}\mspace{11mu} \left( {R_{n,s,i},C_{n,s,i}} \right)} =} \\\{ \\{{R_{n,s,i} = {{mod}\; \left( {i,N_{r}} \right)}},} \\{{T_{n,s,i} = {{mod}\; \left( {{S_{shift} \times R_{n,s,i}},N_{c}} \right)}},} \\{C_{n,s,i} = {{mod}\; \left( {{T_{n,s,i} + \left\lfloor \frac{i}{N_{r}} \right\rfloor},N_{c}} \right)}} \\\}\end{matrix} & \left\lbrack {{Equation}\mspace{14mu} 8} \right\rbrack\end{matrix}$

where S_(shift) is a common shift value for the diagonal-wise readingprocess regardless of N_(xBLOCK) _(_) _(TI)(n,s), and it is determinedby N_(xBLOCK) _(_) _(T1) _(_) _(MAX) given in the PLS2-STAT as followsequation.

                                     [Equation  9]${for}\mspace{14mu} \left\{ {\begin{matrix}{{N_{{xBLOCK\_ TI}{\_ MAX}}^{\prime} = {N_{{xBLOCK\_ TI}{\_ MAX}} + 1}},} & {{{if}\mspace{14mu} N_{x\; {BLOCK\_ TI}{\_ MAX}}{mod}\; 2} = 0} \\{{N_{{xBLOCK\_ TI}{\_ MAX}}^{\prime} = N_{{xBLOCK\_ TI}{\_ MAX}}},} & {{{if}\mspace{14mu} N_{{xBLOCK\_ TI}{\_ MAX}}{mod}\; 2} = 1}\end{matrix},\mspace{20mu} {S_{shift} = \frac{N_{{xBLOCK\_ TI}{\_ MAX}}^{\prime} - 1}{2}}} \right.$

As a result, the cell positions to be read are calculated by acoordinate as z_(n,s,i)=N_(r)C_(n,s,i)+R_(n,s,i).

FIG. 22 illustrates an operation of a twisted row-column blockinterleaver according to another embodiment of the present invention.

More specifically, FIG. 22 illustrates the interleaving array in the TImemory for each TI group, including virtual XFECBLOCKs when N_(xBLOCK)_(_) _(TI)(0,0)=3, N_(xBLOCK) _(_) _(TI)(1,0)=6, N_(xBLOCK) _(_)_(TI)(2,0)=5.

The variable number N_(xBLOCK) _(_) _(TI)(n,s)=N_(r) will be less thanor equal to N_(xBLOCK) _(_) _(TI) _(_) _(MAX). Thus, in order to achievea single-memory deinterleaving at the receiver side, regardless ofN_(xBLOCK) _(_) _(TI)(n,s), the interleaving array for use in a twistedrow-column block interleaver is set to the size ofN_(r)×N_(c)=N_(cells)×N′_(xBLOCK) _(_) _(TI) _(MAX) by inserting thevirtual XFECBLOCKs into the TI memory and the reading process isaccomplished as follow equation.

$\begin{matrix}{{p = 0};} & \left\lbrack {{Equation}\mspace{14mu} 10} \right\rbrack \\{{{{{for}\mspace{14mu} i} = 0};{i < {N_{cells}N_{{xBLOCK\_ TI}{\_ MAX}}^{\prime}}};{i = {i + 1}}}\left\{ {{{GENERATE}\mspace{11mu} \left( {R_{n,s,i},C_{n,s,i}} \right)};{V_{i} = {{{N_{r}C_{n,s,j}} + {R_{n,s,j}\mspace{40mu} {if}\mspace{14mu} V_{i}}} < {N_{cells}{N_{xBlock\_ TI}\left( {n,s} \right)}\mspace{40mu} \left\{ \mspace{59mu} {{Z_{n,s,p} = V_{i}};{p = {p + 1}};}\mspace{50mu} \right\}}}}} \right\}} & \;\end{matrix}$

The number of TI groups is set to 3. The option of time interleaver issignaled in the PLS2-STAT data by DP_TI_TYPE=‘0’, DP_FRAME_INTERVAL=‘1’,and DP_TI_LENGTH=‘1’, i.e., NTI=1, IJUMP=1, and PI=1. The number ofXFECBLOCKs, each of which has Ncells=30 cells, per TI group is signaledin the PLS2-DYN data by NxBLOCK_TI(0,0)=3, NxBLOCK_TI(1,0)=6, andNxBLOCK_TI(2,0)=5, respectively. The maximum number of XFECBLOCK issignaled in the PLS2-STAT data by NxBLOCK_Group_MAX, which leads to└N_(xBLOCK) _(_) _(Group) _(_) _(MAX)/N_(TI)┘=N_(xBLOCK) _(_) _(TI) _(_)_(MAX)=6.

FIG. 23 illustrates a diagonal-wise reading pattern of a twistedrow-column block interleaver according to an embodiment of the presentinvention.

More specifically FIG. 23 shows a diagonal-wise reading pattern fromeach interleaving array with parameters of N′_(xBLOCK) _(_) _(TI) _(_)_(MAX)=7 and Sshift=(7−1)/2=3. Note that in the reading process shown aspseudocode above, if V_(i)≧N_(cells)N_(xBLOCK) _(_) _(TI)(n,s), thevalue of Vi is skipped and the next calculated value of Vi is used.

FIG. 24 illustrates interlaved XFECBLOCKs from each interleaving arrayaccording to an embodiment of the present invention.

FIG. 24 illustrates the interleaved XFECBLOCKs from each interleavingarray with parameters of N′_(xBLOCK) _(_) _(TI) _(_) _(MAX)=7 andSshift=3.

A method for segmenting a file configured to transmit file-basedmultimedia content in a real-time broadcast environment, and consumingthe file segments according to the embodiments of the present inventionwill hereinafter be described in detail.

In more detail, the embodiment provides a data structure fortransmitting the file based multimedia content in the real-timebroadcast environment. In addition, the embodiment provides a method foridentifying not only segmentation generation information of a fileneeded for transmitting file-based multimedia content but alsoconsumption information in a real-time broadcast environment. Inaddition, the embodiment provides a method for segmenting/generating afile needed for transmitting the file-based multimedia content in areal-time broadcast environment. The embodiment provides a method forsegmenting and consuming the file needed for consuming the file-basedmultimedia content.

FIG. 25 illustrates a data processing time when a File Delivery overUnidirectional Transport (FLUTE) protocol is used.

Recently, hybrid broadcast services in which a broadcast network and theInternet network are combined have been widely used. The hybridbroadcast service may

transmit A/V content to the legacy broadcast network, and may transmitadditional data related to A/V content over the Internet. In addition, aservice for transmitting some parts of the A/V content may betransmitted over the Internet has recently been provided.

Since the A/V content is transmitted over a heterogeneous network, amethod for closely combining A/V content data pieces transmitted over aheterogeneous network and a simple cooperation method are needed. Forthis purpose, a communication transmission method capable of beingsimultaneously applied to the broadcast network and the Internet isneeded.

A representative one of the A/V content transmission methods capable ofbeing commonly applied to the broadcast network and the Internet is touse the file-based multimedia content. The file-based multimedia contenthas superior extensibility, is not dependent upon a transmission (Tx)protocol, and has been widely used using a download scheme based on thelegacy Internet.

A File Delivery over Unidirectional Transport protocol (FLUTE) is aprotocol that is appropriate not only for the interaction between thebroadcast network and the Internet but also for transmission of thefile-based multimedia content of a large-capacity file.

FLUTE is an application for unidirectional file transmission based onALC, and is a protocol in which information regarding files needed forfile transmission or information needed for transmission are defined.According to FLUTE, information needed for file transmission andinformation regarding various attributes of a file to be transmittedhave been transmitted through transmission of FDT (File Delivery Table)instance, and the corresponding file is then transmitted.

ALC (Asynchronous Layered Coding) is a protocol in which it is possibleto control reliability and congestion during a file transmission time inwhich a single transmitter transmits the file to several receivers. ALCis a combination of an FEC Building Block for error control, a WEBRCBuilding Block for congestion control, a Layered Coding Transport (LCT)Building Block for session and channel management, and may construct abuilding block according to the service and necessity. ALC is used as acontent transmission protocol such that it can very efficiently transmitdata to many receivers. In addition, ALC has unidirectionalcharacteristics, is transmitted in a limited manner as necessary, doesnot require specific channel and resources for feedback, and can be usednot only in the wireless environmental broadcasting but also in thesatellite environmental broadcasting. Since ALC has no feedback, the FECcode scheme can be entirely or partially applied for reliability,resulting in implementation of reliable services. In addition, an objectto be sent is FEC-encoded according to the FEC scheme, constructs Txblocks and additional symbols formed by the FEC scheme, and is thentransmitted. ALC session may be composed of one or more channels, andseveral receivers select a channel of the session according to thenetwork state and receive a desired object over the selected channel.The receivers can be devoted to receive its own content, and are littleaffected by a state of other receivers or pass loss. Therefore, ALC hashigh stability or can provide a stable content download service usingmulti-layered transmission.

LCT may support transmission (Tx) levels for a reliable contenttransmission (e.g., FLUTE) protocol and a stream transmission protocol.LCT may provide content and characteristics of the basic information tobe transmitted to the receiver. For example, LCT may include a TransportSession Identifier (TSI) field, a Transport Object ID (TOI) field, and aCongestion Control Information (CCI) field.

TSI field may include information for identifying the ALC/LCT session.For example, a channel contained in the session may be identified usinga transmitter IP address and a UDP port. TOI field may includeinformation for identifying each file object. CCI field may includeinformation regarding a used or unused state and information regarding aCongestion Control Block. In addition, LCT may provide additionalinformation and FEC-associated information through an extended header.

As described above, the object (e.g., file) is packetized according tothe FLUTE protocol, and is then packetized according to the ALC/LCTscheme. The packetized ALC/LCT data is re-packetized according to theUDP scheme, and the packetized ALC/LCT/UDP data is packeetized accordingto the IP scheme, resulting in formation of ALC/LCT/UDP/IP data.

The file-based multimedia content may be transmitted not only to theInternet but also to the broadcast network through the contenttransmission protocol such as LCT. In this case, multimedia contentcomposed of at least one object or file may be transmitted and consumedin units of an object or a file through the LCT. A detailed descriptionthereof will hereinafter be described in detail.

FIG. 25(a) shows a data structure based on the FLUTE protocol. Forexample, the multimedia content may include at least one object. Oneobject may include at least one fragment (Fragment 1 or Fragment 2).

A data processing time needed for the FLUTE protocol is shown in FIG.25(b). In FIG. 25(b), the lowest drawing shows the encoding start andend times at which the broadcast signal transmission apparatus starts orstops encoding of one object, and the highest drawing shows thereproduction start and end times at which the broadcast signal receptionapparatus starts or stops reproduction of one object.

The broadcast signal transmission apparatus may start transmission ofthe object upon after completion of generation of the object includingat least one fragment. Therefore, there occurs a transmission standbytime (Dt1) between a start time at which the broadcast signaltransmission apparatus starts to generate the object and another time atwhich the broadcast signal transmission apparatus starts to transmit theobject.

In addition, the broadcast signal reception apparatus stops reception ofthe object including at least one object, and then starts reproductionof the object. Therefore, there occurs a reproduction standby time (Dr1)between a start time at which the broadcast signal reception apparatusstarts reception of the object and another time at which the broadcastsignal reception apparatus starts to reproduce the object.

Therefore, a predetermined time corresponding to the sum of atransmission standby time and a reproduction standby time is neededbefore one object is transmitted from the broadcast signal transmissionapparatus and is then reproduced by the broadcast signal receptionapparatus. This means that the broadcast signal reception apparatusrequires a relatively long initial access time to access thecorresponding object.

As described above, since the FLUTE protocol is used, the broadcastsignal transmission apparatus transmits data on an object basis, thebroadcast signal reception apparatus must receive data of one object andmust consume the corresponding object. Therefore, object transmissionbased on the FLUTE protocol is inappropriate for the real-time broadcastenvironment.

FIG. 26 illustrates a Real-Time Object Delivery over UnidirectionalTransport (ROUTE) protocol stack according to an embodiment of thepresent invention.

The next-generation broadcast system supporting the IP-based hybridbroadcasting may include video data, audio data, subtitle data,signaling data, Electronic Service Guide (ESG) data, and/or NRT contentdata.

Video data, audio data, subtitle data, etc. may be encapsulated in theform of ISO Base Media File (hereinafter referred to as ISO BMFF). Forexample, data encapsulated in the form of ISO BMFF may have a of MPEG(Moving Picture Expert Group)-DASH (Dynamic Adaptive Streaming overHTTP) segment or a format of Media Processing Unit (MPU). Then, dataencapsulated in the form of BMFF may be equally transmitted over thebroadcast network or the Internet or may be differently transmittedaccording to attributes of respective transmission networks.

In the case of the broadcast network, Signaling data, ESG data, NRTContent data, and/or data encapsulated in the form of ISO BMFF may beencapsulated in the form of an application layer transport protocolpacket supporting real-time object transmission. For example, dataencapsulated in the form of ISO BMFF may be encapsulated in the form ofROUTE (Real-Time Object Delivery over Unidirectional Transport) and MMTtransport packet.

Real-Time Object Delivery over Unidirectional Transport (ROUTE) is aprotocol for the delivery of files over IP multicast networks. ROUTEprotocol utilizes Asynchronous Layered Coding (ALC), the base protocoldesigned for massively scalable multicast distribution, Layered CodingTransport (LCT), and other well-known Internet standards.

ROUTE is an enhancement of and functional replacement for FLUTE withadditional features. ROUTE protocol is the reliable delivery of deliveryobjects and associated metadata using LCT packets. The ROUTE protocolmay be used for real-time delivery.

ROUTE functions to deliver signaling messages, Electronic Service Guide(ESG) messages, and NRT content. It is particularly well suited to thedelivery of streaming media for example MPEG-DASH Media Segment files.ROUTE offers lower end-to-end latency through the delivery chain ascompared to FLUTE.

The ROUTE protocol is a generic transport application, providing for thedelivery of any kind of object. It supports rich presentation includingscene descriptions, media objects, and DRM-related information. ROUTE isparticularly well suited to the delivery of real-time media content andoffers many features.

For example, ROUTE offers individual delivery and access to differentmedia components, e.g. language tracks, subtitles, alternative videoviews. And, ROUTE offers support of layered coding by enabling thedelivery on different transport sessions or even ROUTE sessions. And,ROUTE offers support for flexible FEC protection, including multistage.And, ROUTE offers easy combination with MPEGDASH enabling synergybetween broadcast and broadband delivery modes of DASH.

And, ROUTE offers fast access to media when joining a ROUTE and/ortransport session. And, ROUTE offers highly extensible by focusing onthe delivery concept. And, ROUTE offers compatibility with existing IETFprotocols and use of IETFendorsed extension mechanisms.

The ROUTE protocol is split in two major components. First component isa source protocol for delivery of objects or flows/collection ofobjects. Second component is a repair protocol for flexibly protectingdelivery objects or bundles of delivery objects that are deliveredthrough the source protocol.

The source protocol is independent of the repair protocol, i.e. thesource protocol may be deployed without the ROUTE repair protocol.Repair may be added only for certain deployment scenarios, for exampleonly for mobile reception, only in certain geographical areas, only forcertain service, etc.

The source protocol is aligned with FLUTE as defined in RFC 6726 as wellas the extensions defined in 3GPP TS 26.346, but also makes use of someprinciples of FCAST as defined in RFC 6968, for example, that the objectmetadata and the object content may be sent together in a compoundobject.

In addition to basic FLUTE protocol, certain optimizations andrestrictions are added that enable optimized support for real-timedelivery of media data; hence, the name of the protocol. Among others,the source ROUTE protocol provides a real-time delivery of object-basedmedia data. And, the source ROUTE protocol provides a flexiblepacketization, including enabling media-aware packetization as well astransport aware packetization of delivery objects. And, the source ROUTEprotocol provides an independence of files and delivery objects, i.e. adelivery object may be a part of a file or may be a group of files.

Delivery objects are the key component of this protocol as the receiverrecovers delivery objects and passes those to the application. Adelivery object is self-contained for the application, typicallyassociated with certain properties, metadata and timingrelatedinformation that are of relevance for the application. In some cases theproperties are provided in-band along with the object, in other casesthe data needs to be delivered out-of-band in a static or dynamicfashion.

Delivery object may comprise complete or partial files described andaccompanied by “FDT Instance”. And, Delivery object may comprise HTTPEntities (HTTP Entity Header and HTTP Entity Body) and/or packages ofdelivery objects.

Delivery object may be a full file or a byte ranges of a file along withFDT Instance. Delivery object may be delivered in real time or innon-real time (timed or non-timed delivery). If timed, certain real-timeand buffer restrictions apply and specific extension headers may beused. Dynamic and static metadata may be used to describe deliveryobject properties. Delivery object may be delivered in specific datastructures, especially ISO BMFF structures. In this case a media-awarepacketization or a general packetization may be applied. The deliveryformat specifies which of the formats are used in order to provideinformation to the applications. ROUTE repair protocol is FEC based andenabled as an additional layer between the transport layer (e.g., UDP)and the object delivery layer protocol. The FEC reuses concepts of FECFramework defined in RFC 6363, but in contrast to the FEC Framework inRFC 6363 the ROUTE repair protocol does not protect packets, but insteadit protects delivery objects as delivered in the source protocol. EachFEC source block may consist of parts of a delivery object, as a singledelivery object (similar to FLUTE) or by multiple delivery objects thatare bundled prior to FEC protection. ROUTE FEC makes use of FEC schemesin a similar sense to that defined in RFC 5052, and uses the terminologyof that document. The FEC scheme defines the FEC encoding and decoding,and it defines the protocol fields and procedures used to identifypacket payload data in the context of the FEC scheme.

In ROUTE all packets are LCT packets as defined in RFC 5651. Source andrepair packets may be distinguished by at least one of a ROUTE session,a LCT transport session, and/or a PSI bit. Different ROUTE sessions arecarried on different IP/UDP port combinations. Different LCT transportsessions use different TSI values in the LCT header. And, if source andrepair packets are carried in the same LCT transport session, they maybe distinguished by the PSI bit in the LCT. This mode of operation ismostly suitable for FLUTE compatible deployments.

ROUTE defines the source protocol including packet formats, sendingbehavior and receiving behavior. And, ROUTE defines the repair protocol.And, ROUTE defines a metadata for transport session establishment and ametadata for object flow delivery. And ROUTE defines recommendations forMPEG DASH configuration and mapping to ROUTE to enable rich andhigh-quality linear TV broadcast services.

The scope of the ROUTE protocol is the reliable delivery of deliveryobjects and associated metadata using LCT packets. The objects are madeavailable to the application through a Delivery Object Cache. Theimplementation of this cache is application dependent.

The ROUTE protocol focuses on the format of the LCT packets to deliverthe delivery objects and the reliable delivery of the delivery objectusing a repair protocol based on FEC. And, the ROUTE protocol focuses onthe definition and delivery of object metadata along with the deliveryobjects to enable the interface between the delivery object cache andthe application. And, the ROUTE protocol focuses on the ROUTE and LCTsession description to establish the reception of objects along withtheir metadata. And, the ROUTE protocol focuses on the normative aspects(formats, semantics) of auxiliary information to be delivered along withthe packets to optimize the performance for specific applications, e.g.,real-time delivery.

In addition, the ROUTE protocol provides recommended mappings ofspecific DASH Media Presentation formats to ROUTE delivery as well assuitable DASH formats to be used for the delivery. The key issue is thatby using ROUTE, the DASH media formats may be used as is. Thisarchitectural design enables converged unicast/broadcast services.

In sender operation of the ROUTE protocol, a ROUTE session isestablished that delivers LCT packets. These packets may carry sourceobjects or FEC repair data. A source protocol consists of one or moreLCT sessions, each carrying associated objects along with theirmetadata. The metadata may be statically delivered in the LCT SessionInstance Description (LSID) or may be dynamically delivered, either as acompound object in the Entity Mode or as LCT extension headers in packetheaders. The packets are carried in ALC using a specific FEC scheme thatpermits flexible fragmentation of the object at arbitrary byteboundaries. In addition, delivery objects may be FEC protected, eitherindividually or in bundles. In either case, the bundled object isencoded and only the repair packets are delivered. In combination withthe source packets, this permits the recovery delivery object bundles.Note that one or multiple repair flows may be generated, each withdifferent characteristics, for example to supported different latencyrequirements, different protection requirements, etc.

A DMD (Dynamic MetaData) is metadata to generate FDT equivalentdescriptions dynamically at the client. It is carried in theentity-header in the Entity Mode and is carried in the LCT header inother modes of delivery.

The ROUTE protocol supports different protection and delivery schemes ofthe source data. It also supports all existing use cases for NRTdelivery, as it can be deployed in a backward-compatible mode.

The ROUTE session is associated to an IP address/port combination.Typically, by joining such a session, all packets of the session can bereceived and the application protocol may apply further processing. EachROUTE session constitutes of one or multiple LCT transport sessions. LCTtransport sessions are a subset of a ROUTE session. For media delivery,an LCT transport session typically would carry a media component, forexample a DASH Representation. From the perspective of broadcast DASH,the ROUTE session can be considered as the multiplex of LCT transportsessions that carry constituent media components of one or more DASHMedia Presentations. Within each LCT transport session, one or multipleobjects are carried, typically objects that are related, e.g. DASHSegments associated to one Representation. Along with each object,metadata properties are delivered such that the objects can be used inapplications. Applications include, but are not limited to, DASH MediaPresentations, HTML-5 Presentations, or any other object-consumingapplication.

The ROUTE sessions may be bounded or unbounded from the temporalperspective.

The ROUTE session contains one or multiple LCT transport sessions. Eachtransport session is uniquely identified by a unique Transport SessionIdentifier (TSI) value in the LCT header.

Before a receiver can join a ROUTE session, the receiver needs to obtaina ROUTE Session Description. The ROUTE Session Description contains atleast one of the sender IP address, the address and port number used forthe session, the indication that the session is a ROUTE session and thatall packets are LCT packets, and/or other information that is essentialto join and consume the session on an IP/UDP level.

The Session Description could also include, but is not limited to, thedata rates used for the ROUTE session and any information on theduration of the ROUTE session. The Session Description could be in aform such as the Session Description Protocol (SDP) as defined in RFC4566 or XML metadata as defined in RFC 3023. It might be carried in anysession announcement protocol using a proprietary session controlprotocol, located on a web page with scheduling information, or conveyedvia email or other out-of-band methods.

Transport sessions are not described in the ROUTE session description,but in the LCT Session Instance Description (LSID). Transport sessions(i.e., LCT transport sessions or simply LCT sessions) may contain eitheror both of Source Flows and Repair Flows. The Source Flows carry sourcedata. And, the Repair Flows carry repair data.

The LCT transport sessions contained in a ROUTE session are described bythe LCT Session Instance description (LSID). Specifically, it defineswhat is carried in each constituent LCT transport session of the ROUTEsession. Each transport session is uniquely identified by a TransportSession Identifier (TSI) in the LCT header.

The LSID describes all transport sessions that are carried on this ROUTEsession. The LSID may be delivered in the same ROUTE session containingthe LCT transport sessions or it may be delivered by means outside theROUTE session, e.g. through unicast or through a different ROUTEsession. In the former case, the LSID shall be delivered on a dedicatedLCT transport session with TSI=0, and furthermore, it shall be adelivery object identified by TOI=0. For any object delivered on TSI=0,the Entity Mode should be used. If those objects are not delivered inthe Entity Mode, then the LSID must be recovered prior to obtaining theextended FDT for the received object.

The Internet Media Type of the LSID is application/xml+route+lsid.

The LSID may reference other data fragments. Any object that isreferenced in the LSID may also be delivered on TSI=0, but with adifferent value of TOI than the LSID itself, or it may be delivered on aseparate LCT session with dedicated TSI≠0.

The LSID element may contain version attribute, validity attribute,and/or expiration attribute. The LSID element may be updated accordinglyusing version attribute as well as validity attribute and expirationattribute. For example certain transport sessions may be terminatedafter some time and new session may start.

The version attribute indicates a version of this LSID element. Theversion is increased by one when the descriptor is updated. The receivedLSID element with highest version number is the currently valid version.

The validity attribute indicates date and/or time from which the LSIDelement is valid. The validity attribute may or may not be present. Ifnot present, the receiver should assume the LSID element version isvalid immediately.

The expiration attribute indicates date and time when the LSID elementexpires. The expiration attribute may or may not be present. If notpresent the receiver should assume the LSID element is valid for alltime, or until it receives a newer LSID element with an associatedexpiration value.

The LSID element may contain at least one TransportSession element.TransportSession element provides information about LCT transportsessions. Each TransportSession element may contain tsi attribute,SourceFlow element, and/or RepairFlow element.

tsi attribute specifies the transport session identifier. The sessionidentifiers must not be 0. SourceFlow element provides information of asource flow carried on the transport session. RepairFlow elementprovides information of a repair flow carried on the transport session.

Thereafter, data encapsulated in the form of the application layertransport protocol packet may be packetized according to the IP/UDPscheme. The data packetized by the IP/UDP scheme may be referred to asthe IP/UDP datagram, and the IP/UDP datagram may be loaded on thebroadcast signal and then transmitted.

In the case of the Internet, data encapsulated in the form of ISO BMFFmay be transferred to the receiver according to the streaming scheme.For example, the streaming scheme may include MPEG-DASH.

The signaling data may be transmitted using the following methods.

In the case of the broadcast network, signaling data may be transmittedthrough a specific data pipe (hereinafter referred to as DP) of atransport frame (or frame) applied to a physical layer of thenext-generation broadcast transmission system and broadcast networkaccording to attributes of the signaling data. For example, thesignaling format may be encapsulated in the form of a bitstream orIP/UDP datagram.

In the case of the Internet, the signaling data may be transmitted as aresponse to a request of the receiver.

ESG data and NRT content data may be transmitted using the followingmethods.

In the case of the broadcast network, ESG data and NRT content data maybe encapsulated in the form of an application layer transport protocolpacket. Thereafter, data encapsulated in the form of the applicationlayer transport protocol packet may be transmitted in the same manner asdescribed above.

In the case of the Internet, ESG data and NRT content data may betransmitted as a response to the request of the receiver.

The physical layers (Broadcast PHY and broadband PHY) of the broadcastsignal transmission apparatus according to the embodiment may be shownin FIG. 1. In addition, the physical layers of the broadcast signalreception apparatus may be shown in FIG. 9.

The signaling data and the IP/UDP datagram may be transmitted through aspecific data pipe (hereinafter referred to as DP) of a transport frame(or frame). For example, the input formatting block 1000 may receive thesignaling data and the IP/UDP datagram, each of the signaling data andthe IP/UDP datagram may be demultiplexed into at least one DR The outputprocessor 9300 may perform the operations opposite to those of the inputformatting block 1000.

The following description relates to an exemplary case in which dataencapsulated in the form of ISO BMFF is encapsulated in the form ofROUTE transport packet, and a detailed description of the exemplary casewill hereinafter be described in detail.

<Data Structure for Real-Time File Generation and Consumption>

FIG. 32 illustrates a data structure of file-based multimedia contentaccording to an embodiment of the present invention.

The data structure of the file-based multimedia content according to theembodiment is shown in FIG. 32. The term “file-based multimedia content”may indicate multimedia content composed of at least one file.

The multimedia content such as a broadcast program may be composed ofone presentation. The presentation may include at least one object. Forexample, the object may be a file. In addition, the object may includeat least one fragment.

In accordance with the embodiment, the fragment may be a data unitcapable of being independently decoded and reproduced without dependingon the preceding data. For example, the fragment including video datamay begin from an IDR picture, and header data for parsing media datadoes not depend on the preceding fragment. The fragment according to theembodiment may be divided and transmitted in units of at least onetransfer block (TB).

In accordance with the embodiment, the transfer block (TB) may be aminimum data unit capable of being independently and transmitted withoutdepending on the preceding data. In addition, the TB may be asignificant data unit configured in the form of a variable-sized GOP orchunk. For example, the TB may include at least one chunk composed ofthe same media data as in GOP of video data. The term “chunk” mayindicate a segment of the content. In addition, the TB may include atleast one source block.

GOP is a basic unit for performing coding used in video coding and is adata unit with a variable size indicating a set of frames including atleast one I-frame. According to an embodiment of the present invention,media data is transmitted in an object internal structure unit as anindependently meaningful data unit, and thus GOP may include Open GOPand Closed GOP.

In Open GOP, B-frame in one GOP may refer to I-frame or P-frame of anadjacent GOP. Thus, Open GOP can seriously enhance coding efficiency. InClosed GOP, Bframe or P-frame may refer to only a frame in thecorresponding GOP and may not refer to frames in GOPs except for thecorresponding GOP.

The TB may include at least one data, and respective data pieces mayhave the same or different media types. For example, the media type mayinclude an audio type and a video type. That is, the TB may also includeone or more data pieces having different media types in the same manneras in the audio and video data.

The fragment according to the embodiment may include a fragment headerand a fragment payload.

The fragment header may include timing information and indexinginformation to parse the above-mentioned chunks. The fragment header maybe comprised of at least one TB. For example, the fragment header may becontained in one TB. In addition, at least one chunk data constructingthe fragment payload may be contained in at least one TB. As describedabove, the fragment header and the fragment payload may be contained inat least one TB.

The TB may be divided into one or more symbols. At least one symbol maybe packetized. For example, the broadcast signal transmission apparatusaccording to the embodiment may packetize at least one symbol into theLCT packet.

The broadcast signal transmission apparatus according to the embodimentmay transmit the packetized data to the broadcast signal receptionapparatus.

FIG. 27 illustrates a media segment structure of MPEG-DASH to which thedata structure is applied.

Referring to FIG. 27, the data structure according to the embodiment isapplied to a media segment of MPEG-DASH.

The broadcast signal transmission apparatus according to the embodimentinclude multimedia contents having a plurality of qualities in theserver, provides the multimedia contents appropriate for the userbroadcast environment and the environment of the broadcast signalreception apparatus, such that it can provide the seamless real-timestreaming service. For example, the broadcast signal transmissionapparatus may provide the real-time streaming service using MPEG-DASH.

The broadcast signal transmission apparatus can dynamically transmitXML-type MPD (Media Presentation Description) and a segment ofbinary-format transmit (Tx) multimedia content to the broadcast signalreception apparatus using the ROUTE protocol according to the broadcastenvironment and the environment of the broadcast signal receptionapparatus.

MPD is comprised of a hierarchical structure, and may include astructural function of each layer and roles of each layer.

The segment may include a media segment. The media segment may be a dataunit having a media-related object format being separated per quality orper time to be transmitted to the broadcast signal reception apparatusso as to support the streaming service. The media segment may includeinformation regarding a media stream, at least one access unit, andinformation regarding a method for accessing Media Presentationcontained in the corresponding segment such as a presentation time orindex. In addition, the media segment may be divided into at least onesubsegment by the segment index.

MPEG-DASH content may include at least one media segment. The mediasegment may include at least one fragment. For example, the fragment maybe the abovementioned subsegment. As described above, the fragment mayinclude a fragment header and a fragment payload.

The fragment header may include a segment index box (sidx) and a moviefragment box (moof). The segment index box may provide an initialpresentation time of media data present in the corresponding fragment, adata offset, and SAP (Stream Access Points) information. The moviefragment box may include metadata regarding a media data box (mdat). Forexample, the movie fragment box may include timing, indexing, anddecoding information of a media data sample contained in the fragment.

The fragment payload may include the media data box (mdat). The mediadata box (mdat) may include actual media data regarding thecorresponding media constituent elements (video and audio data, etc.).

The encoded media data configured on a chunk basis may be contained inthe media data box (mdat) corresponding to the fragment payload. Asdescribed above, samples corresponding to the same track may becontained in one chunk.

The broadcast signal transmission apparatus may generate at least one TBthrough fragment segmentation. In addition, the broadcast signaltransmission apparatus may include the fragment header and the payloaddata in different TBs so as to discriminate between the fragment headerand the payload data.

In addition, the broadcast signal transmission apparatus may transmit atransfer block (TB) divided on a chunk basis so as to segment/transmitdata contained in the fragment payload. That is, the broadcast signaltransmission apparatus according to the embodiment may generate a TB ina manner that a border of the chunk is identical to a border of the TB.

Thereafter, the broadcast signal transmission apparatus segments atleast one TB such that it can generate at least one symbol. All symbolscontained in the object may be identical to each other. In addition, thelast symbol of TB may include a plurality of padding bytes such that allsymbols contained in the object have the same length.

The broadcast signal transmission apparatus may packetize at least onesymbol. For example, the broadcast signal transmission apparatus maygenerate the LCT packet on the basis of at least one symbol.

Thereafter, the broadcast signal transmission apparatus may transmit thegenerated LCT packet.

In accordance with the embodiment, the broadcast signal transmissionapparatus first generates the fragment payload, and generates thefragment header so as to generate the fragment. In this case, thebroadcast signal transmission apparatus may generate a TB correspondingto media data contained in the fragment payload. For example, at leastTB corresponding to media data contained in the media data box (mdat)may be sequentially generated on a chunk basis. Thereafter, thebroadcast signal transmission apparatus may generate the TBcorresponding to the fragment header.

The broadcast signal transmission apparatus may transmit the generatedTB according to the generation order so as to broadcast the mediacontent in real time. In contrast, the broadcast signal receptionapparatus according to the embodiment first parses the fragment header,and then parses the fragment payload.

The broadcast signal transmission apparatus may transmit data accordingto the parsing order when media data is pre-encoded or TB ispre-generated.

FIG. 29 illustrates a data processing time using a ROUTE protocolaccording to an embodiment of the present invention.

FIG. 29(a) shows the data structure according to the embodiment. Themultimedia data may include at least one object. Each object may includeat least one fragment. For example, one object may include two fragments(Fragment1 and Fragment 2).

The broadcast signal transmission apparatus may segment the fragmentinto one or more TBs. The TB may be a source block, and the followingdescription will hereinafter be given on the basis of the source block.

For example, the broadcast signal transmission apparatus may segment thefragment 1 into three source blocks (Source Block 0, Source Block 1, andSource Block 2), and may segment the fragment 2 into three source blocks(Source Block 3, Source Block 4, Source Block 5).

The broadcast signal transmission apparatus may independently transmiteach segmented source block. The broadcast signal transmission apparatusmay start transmission of each source block generated when or just aftereach source block is generated.

For example, the broadcast signal transmission apparatus can transmitthe source block 0 (S0) after the source block 0 (S0) has been generatedfor a predetermined time (te0˜te1). The transmission start time (td0) ofthe source block 0 (S0) may be identical to the generation completiontime (td0) or may be located just after the generation completion time(td0). Likewise, the broadcast signal transmission apparatus maygenerate the source blocks 1 to 5 (Source Block 1 (S1) to Source Block 5(S5)), and may transmit the generated source blocks 1 to 5.

Therefore, the broadcast signal transmission apparatus according to theembodiment may generate a transmission standby time (Dt2) between astart time of generating one source block and another start time oftransmitting the source block. The transmission standby time (Dt2)generated by the broadcast signal transmission apparatus is relativelyshorter than the transmission standby time (Dt1) generated by theconventional broadcast signal transmission apparatus. Therefore, thebroadcast signal transmission apparatus according to the embodiment cangreatly reduce a transmission standby time as compared to theconventional broadcast signal transmission apparatus.

The broadcast signal reception apparatus according to the embodimentreceives each segmented source block, and combines the received sourceblocks, such that it can generate at least one fragment. For example,the broadcast signal reception apparatus may receive the source block 0(S0), the source block 1 (S1), and the source block 2 (S2), and combinethe received three source blocks (S0, S1, S2) so as to generate thefragment 1. In addition, the broadcast signal reception apparatusreceives the source block 3 (S3), the source block 4 (S4), and thesource block 5 (S5), and combines the received three source blocks (S3,S4, S5) so as to generate the fragment 2.

The broadcast signal reception apparatus may separately generate eachfragment. The broadcast signal reception apparatus may reproduce eachfragment when or just after each fragment is generated. Alternatively,the broadcast signal reception apparatus may reproduce each fragmentwhen or just after the source block corresponding to each fragment istransmitted.

For example, the broadcast signal reception apparatus may generate thefragment 1 after receiving the source blocks 0 to 2 (S0˜S2) during apredetermined time (td0˜td3). For example, after the broadcast signalreception apparatus receives the source blocks 0 to 2 (S0˜S2) during apredetermined time (td0˜td3), it can generate the fragment 1.Thereafter, the broadcast signal reception apparatus may reproduce thegenerated fragment 1. The reproduction start time (tp0) of the fragment1 may be identical to the generation time of the fragment 1 or may belocated after the generation time of the fragment 1. In addition, areproduction start time (tp0) of the fragment 1 may be identical to areception completion time of the source block 2 (S2) or may be locatedjust after the reception completion time of the source block 2 (S2).

In the same manner, after the broadcast signal reception apparatusaccording to the embodiment receives the source blocks 3 to 5 (S3˜S5)during a predetermined time (td3˜td6), it may generate the fragment 2.Thereafter, the broadcast signal reception apparatus may reproduce thefragment 2.

However, the scope or spirit of the present invention is not limitedthereto, and the broadcast signal reception apparatus according to theembodiment may receive the source block and may reproduce data in unitsof a received source block as necessary.

Therefore, the broadcast signal reception apparatus according to theembodiment may generate a reproduction standby time (Dr2) between areception start time of one fragment and a reproduction start time ofthe fragment. The reproduction standby time (Dr2) generated by thebroadcast signal reception apparatus is relatively shorter than thereproduction standby time (Dr2) generated by the broadcast signalreception apparatus. Therefore, the broadcast signal reception apparatusaccording to the embodiment can reduce a reproduction standby time ascompared to the conventional broadcast signal reception apparatus.

As described above, a predetermined time corresponding to the sum of atransmission standby time and a reproduction standby time may beconsiderably reduced. Here, the predetermined time may be needed whenone TB is transmitted from the broadcast signal transmission apparatusand is then reproduced by the broadcast signal reception apparatus. Thismeans that an initial access time during which the broadcast signalreception apparatus initially approaches the corresponding object isconsiderably reduced.

In case of using the ROUTE protocol, the broadcast signal transmissionapparatus may transmit data in units of a TB, and the broadcast signalreception apparatus may reproduce the received data in units of a TB ora fragment. As a result, a total time from an acquisition time ofmultimedia content to a content display time for a user can be reduced,and an initial access time required when the user approaches thebroadcast channel can also be reduced.

Therefore, TB transmission based on the ROUTE protocol is appropriatefor the realtime broadcast environment.

<Method for Identifying File Segmentation Generation and ConsumptionInformation>

FIG. 30 illustrates a Layered Coding Transport (LCT) packet structurefor file transmission according to an embodiment of the presentinvention.

An application layer transport session may be composed of an IP addressand a port number. If the application layer transport session is theROUTE protocol, the ROUTE session may be composed of one or more LCT(Layered Coding Transport) sessions. For example, if one media componentis transmitted through one LCT transport session, at least one mediacomponent may be multiplexed and transmitted through one applicationlayer transport session. In addition, at least one transport object maybe transmitted through one LCT transport session.

Referring to FIG. 30, if the application layer transmission protocol isbased on the LCT, each field of the LCT packet may indicate thefollowing information.

The LCT packet may include an LCT version number field (V), a congestioncontrol flag field (C), a reserved field (R), a transport sessionidentifier flag field (S), a transport object identifier flag field (O),a half-word flag field (H), a sender current time present flag field(T), an expected residual time present flag field (R), a close sessionflag field (A), a close object flag field (B), an LCT header lengthfield (HDR_LEN), a codepoint field (CP), a congestion controlinformation field (CCI), a transport session identifier field (TSI), atransport object identifier field (TOI), a header extensions field, anFEC payload ID field, and/or an encoding symbol(s) field.

LCT version number field (V) indicates the protocol version number. Forexample, this field indicates the LCT version number. The version numberfield of the LCT header MUST be interpreted as the ROUTE version numberfield. This version of ROUTE implicitly makes use of version ‘1’ of theLCT building block. For example, the version number is ‘0001b’.

Congestion control flag field (C) indicates the length of CongestionControl Information field. C=0 indicates the Congestion ControlInformation (CCI) field is 32-bits in length. C=1 indicates the CCIfield is 64-bits in length. C=2 indicates the CCI field is 96-bits inlength. C=3 indicates the CCI field is 128-bits in length.

Reserved field (R) reserved for future use. For example, Reserved field(R) may be Protocol-Specific Indication field (PSI). Protocol-SpecificIndication field (PSI) may be used as an indicator for a specificpurpose in the LCT higher protocol. PSI field indicates whether thecurrent packet is a source packet or an FEC repair packet. As the ROUTEsource protocol only delivers source packets, this field shall be set to‘10 b’.

Transport Session Identifier flag field(S) indicates the length ofTransport Session Identifier field.

Transport Object Identifier flag field (O) indicates the length ofTransport Object Identifier field. For example, the object may indicateone file; and the TOI may indicate ID information of each object, and afile having TOI=0 may be referred to as FDT.

Half-word flag field (H) may indicate whether half-word (16 bits) willbe added to the length of TSI or TOI field.

Sender Current Time present flag field (T) indicates whether the SenderCurrent Time (SCT) field is present or not. T=0 indicates that theSender Current Time (SCT) field is not present. T=1 indicates that theSCT field is present. The SCT is inserted by senders to indicate toreceivers how long the session has been in progress.

Expected Residual Time present flag field (R) indicates whether theExpected Residual Time (ERT) field is present or not. R=0 indicates thatthe Expected Residual Time (ERT) field is not present. R=1 indicatesthat the ERT field is present. The ERT is inserted by senders toindicate to receivers how much longer the session/object transmissionwill continue.

Close Session flag field (A) may indicate whether session completion oran impending state of the session completion.

Close Object flag field (B) may indicate completion or impendingcompletion of a transmitting object.

LCT header length field (HDR_LEN):indicates total length of the LCTheader in units of 32-bit words.

Codepoint field (CP) indicates the type of the payload that is carriedby this packet. Depending on the type of the payload, additional payloadheader may be added to prefix the payload data.

Congestion Control Information field (CCI) may be used to transmitcongestion control information (e.g., layer numbers, logical channelnumbers, sequence numbers, etc.). The Congestion Control Informationfield in the LCT header contains the required Congestion ControlInformation.

Transport Session Identifier field (TSI) is a unique ID of a session.The TSI uniquely identifies a session among all sessions from aparticular sender. This field identifies the Transport Session in ROUTE.The context of the Transport Session is provided by the LSID (LCTSession Instance description).

LSID defines what is carried in each constituent LCT transport sessionof the ROUTE session. Each transport session is uniquely identified by aTransport Session Identifier (TSI) in the LCT header. LSID may betransmitted through the same ROUTE session including LCT transportsessions, and may also be transmitted through Web. LSID may betransmitted through the same ROUTE session including LCT transmissionsessions and may also be transmitted through a communication network, abroadcast network, the Internet, a cable network, and/or a satellitenetwork. The scope or spirit of a transmission unit of LSID is notlimited thereto. For example, LSID may be transmitted through a specificLCT transport session having TSI=0. LSID may include signalinginformation regarding all transport sessions applied to the ROUTEsession. LSID may include LSID version information and LSID validityinformation. In addition, LSID may include a transport session throughwhich the LCT transport session information is transmitted. Thetransport session information may include TSI information foridentifying the transport session, source flow information that istransmitted to the corresponding TSI and provides information regardinga source flow needed for source data transmission, repair flowinformation that is transmitted to the corresponding TSI and providesinformation regarding a repair flow needed for transmission of repairdata, and transport session property information including additionalcharacteristic information of the corresponding transport session.

Transport Object Identifier field (TOI) is a unique ID of the object.The TOI indicates which object within the session this packet pertainsto. This field indicates to which object within this session the payloadof the current packet belongs to. The mapping of the TOI field to theobject is provided by the Extended FDT.

Extended FDT specifies the details of the file delivery data. This isthe extended FDT instance. The extended FDT together with the LCT packetheader may be used to generate the FDT-equivalent descriptions for thedelivery object. The Extended FDT may either be embedded or may beprovided as a reference. If, provided as a reference the Extended FDTmay be updated independently of the LSID. If referenced, it shall bedelivered as in-band object on TOI=0 of the included source flow.

Header Extensions field may be used as an LCT header extension part fortransmission of additional information. The Header Extensions are usedin LCT to accommodate optional header fields that are not always used orhave variable size.

For example, EXT_TIME extension is used to carry several types of timinginformation. It includes general purpose timing information, namely theSender Current Time (SCT), Expected Residual Time (ERT), and Sender LastChange (SLC) time extensions described in the present document. It canalso be used for timing information with narrower applicability (e.g.,defined for a single protocol instantiation); in this case, it will bedescribed in a separate document.

FEC Payload ID field may include ID information of Transmission Block orEncoding Symbol. FEC Payload ID may indicate an ID to be used when theabove file is FEC-encoded. For example, if the FLUTE protocol file isFEC-encoded, FEC Payload ID may be allocated for a broadcast station orbroadcast server configured to identify the FEC-encoded FLUTE protocolfile.

Encoding Symbol(s) field may include Transmission Block or Encodingsymbol data.

The packet payload contains bytes generated from an object. If more thanone object is carried in the session, then the Transmission Object ID(TOI) within the LCT header MUST be used to identify from which objectthe packet payload data is generated.

The LCT packet according to the embodiment may include Real Time SupportExtension field (EXT_RTS) corresponding to an extension format of aHeader Extensions field. EXT_RTS may include segmentation generation andconsumption information of the file, and will hereinafter be referred toas fragment information. The LCT packet according to the embodimentincludes EXT_RTS corresponding to an extension format of the HeaderExtensions field, and may support real-time file transmission andconsumption information using a method compatible with the legacy LCT.

The fragment information (EXT_RTS) according to the embodiment mayinclude Header Extension Type field (HET), Fragment Start Indicatorfield (SI), Fragment Header flag field (FH), and Fragment HeaderComplete Indicator field (FC).

Header Extension Type field (HET) may indicate the corresponding HeaderExtension type. The HET field may be an integer of 8 bits. Basically, ifHET for use in LCT is in the range of 0 to 127, a variable-length headerextension in units of a 32-bit word is present, and the length of HET iswritten in the Header Extension Length field (HEL) subsequent to HET. IfHET is in the range of 128 to 255, Header Extension may have a fixedlength of 32 bits.

The fragment information (EXT_RTS) according to the embodiment has afixed length of 32 bits, such that the corresponding Header Extensiontype may be identified using one unique value from among the values of128 to 255, and may identify the corresponding Header Extension type.

SI field may indicate that the corresponding lCT packet includes a startpart of the fragment. If a user in the broadcast environment approachesa random access of a file through which the corresponding file-basedmultimedia content is transmitted, packets having “SI field=0” fromamong the initial reception packets are discarded, the packets startingfrom a packet having “SI field=1” starts parsing, so that the packetprocessing efficiency and the initial delay time can be reduced.

FH field may indicate that the corresponding LCT packet includes thefragment header part. As described above, the fragment header ischaracterized in that a generation order and a consumption order of thefragment header are different from those of the fragment payload. Thebroadcast signal reception apparatus according to the embodiment mayrearrange transmission blocks sequentially received on the basis of theFH field according to the consumption order, so that it can regeneratethe fragment.

FC field may indicate that the corresponding packet includes the lastdata of the fragment. For example, if the fragment header is transmittedafter the fragment payload is first transmitted, the FC field mayindicate inclusion of the last data of the fragment header. If thefragment header is first transmitted and the fragment payload is thentransmitted, the FC field may indicate inclusion of the last data of thefragment payload. The following description will hereinafter disclose anexemplary case in which the fragment payload is first transmitted andthe fragment is then transmitted.

If the broadcast signal reception apparatus receives the packet having“FC field=1”, the broadcast signal reception apparatus may recognizereception completion of the fragment header, and may perform fragmentrecovery by combining the fragment header and the fragment payload.

Padding Bytes field (PB) may indicate the number of padding bytescontained in the corresponding LCT packet. In the legacy LCT, all LCTpackets corresponding to one object must be identical to each other.However, when a transmission block (TB) is divided according to the dataconstruction method, the last symbol of each TB may have a differentlength. Therefore, the broadcast signal transmission apparatus accordingto the embodiment fills a residual part of the packet with paddingbytes, such that it can support the real-time file transmission using afixed-length packet according to the method compatible with the legacyLCT.

Reserved field reserved for future use.

FIG. 31 illustrates a structure of an LCT packet according to anotherembodiment of the present invention.

Some parts of FIG. 31 are substantially identical to those of FIG. 30,and as such a detailed description thereof will herein be omitted, suchthat FIG. 31 will hereinafter be described centering on a differencebetween FIG. 30 and FIG. 31.

Referring to FIG. 31, fragment information (EXT_RTS) according toanother embodiment may include a Fragment Header Length field (FHL)instead of the FC field shown in FIG. 30.

FHL field indicates the number of constituent symbols of the fragment,so that it can provide specific information as to whether reception ofthe fragment is completed. The FHL field may indicate a total number ofsymbols corresponding to respective fragments including the fragmentheader and the fragment payload. In addition, the FHL field may indicatea total number of symbols to be transmitted later from among thefragment header and the fragment payload.

For example, if the fragment payload is first transmitted and thefragment header is then transmitted, the FHL field may indicate a totalnumber of symbols corresponding to the fragment header. In this case,the FHL field may indicate the length of the fragment header.

If the fragment header is first transmitted and the fragment payload isthen transmitted, the FHL field may indicate a total number of symbolscorresponding to the fragment payload. In this case, the FHL field mayindicate the length of the fragment payload.

The following description will hereinafter disclose an exemplary case inwhich the fragment payload is first transmitted and the fragment headeris then transmitted.

The broadcast signal reception apparatus according to another embodimentmay receive the LCT packet including the fragment header correspondingto the number of symbols displayed on the FHL field. The broadcastsignal reception apparatus checks the number of reception times of theLCT packet including the fragment header, so that it can identifyreception completion of the fragment header. Alternatively, thebroadcast signal reception apparatus checks the number of TBscorresponding to the fragment header, so that it can identify receptioncompletion of the fragment header.

<Method for Identifying Segmentation Generation and SegmentationConsumption Information of File>

FIG. 32 illustrates real-time broadcast support information signalingbased on FDT according to an embodiment of the present invention.

Referring to FIG. 32, the present invention relates to a method foridentifying segmentation generation and segmentation consumptioninformation of file-based multimedia content in a real-time broadcastenvironment. The segmentation generation and segmentation consumptioninformation of the file-based multimedia content may include theabove-mentioned data structure and LCT packet information.

The broadcast signal transmission apparatus may further transmitadditional signalling information so as to identify segmentationgeneration information and segmentation consumption information of thefile. For example, the signalling information may include metadata adout-of-band signaling information.

A method for transmitting signaling information regarding the real-timebroadcast support information according to the embodiment is shown inFIG. 32.

The broadcast signal transmission apparatus according to the embodimentmay transmit signaling information either through a File Delivery Table(FDT) level or through a file-level Real-Time-Support attribute. IfReal-Time-Support is set to 1, objects written in the corresponding FDTlevel or File level may include the abovementioned data structure andpacket information, such that file segmentation generation andconsumption in the real-time broadcast environment can be indicated.

FIG. 33 is a block diagram illustrating a broadcast signal transmissionapparatus according to an embodiment of the present invention.

Referring to FIG. 33, the broadcast signal transmission apparatus fortransmitting broadcast signals including multimedia content using thebroadcast network may include a signaling encoder C21005, a TransmissionBlock Generator C21030, and/or a Transmitter C21050.

The signaling encoder C21005 may generate signaling information. Thesignaling information may indicate whether multimedia content will betransmitted in real time. The signaling information may indicate thatthe above-mentioned multimedia content is transmitted from among atleast one of the file level and the FDT level in real time. When thesignaling information indicates that multimedia content is transmittedat a power level in real time, all data belonging to the correspondingfile can be, transmitted in real time. When the signaling informationindicates that multimedia content is transmitted at an FDT level in realtime, all files or data belonging to the corresponding FDT can betransmitted in real time.

If the signaling information indicates real-time transmission of themultimedia content, the Transmission Block Generator C21030 may dividethe file contained in the multimedia content into one or more TBscorresponding to data that is independently encoded and transmitted.

The transmitter C21050 may transmit the transmission block (TB).

A detailed description thereof will hereinafter be described withreference to FIG. 34.

FIG. 34 is a block diagram illustrating a broadcast signal transmissionapparatus according to an embodiment of the present invention.

Referring to FIG. 34, the broadcast signal transmission apparatus fortransmitting broadcast signals including multimedia content using thebroadcast network according to the embodiment may include a signalingencoder (not shown), a Media Encoder C21010, a Fragment GeneratorC21020, a Transmission Block Generator C21030, a Packetizer C21040,and/or a Transmitter C21050.

The signaling encoder (not shown) may generate signaling information.The signaling information may indicate whether multimedia content willbe transmitted in real time.

Media Encoder C21010 may encode multimedia content so that it cangenerate media data using the encoded multimedia content. Hereinafter,the term “media data” will be referred to as data.

Fragment Generator C21020 may segment each file constructing themultimedia content, so that it can generate at least one fragmentindicating a data unit that is independently encoded and reproduced.

Fragment Generator C21020 may generate the fragment payload constructingeach fragment and then generate the fragment header.

Fragment Generator C21020 may buffer media data corresponding to thefragment payload. Thereafter, the Fragment Generator C21020 may generatea chunk corresponding to the fragment payload on the basis of thebuffered media data. For example, the chunk may be a variable-sized dataunit composed of the same media data as in GOP of video data.

If generation of the chunk corresponding to the fragment payload is notcompleted, the Fragment Generator C21020 continuously buffers the mediadata, and completes generation of the chunk corresponding to thefragment payload.

Fragment Generator C21020 may determine whether data corresponding tothe fragment payload is generated as a chunk whenever the chunk isgenerated.

If the chunk corresponding to the fragment payload is completedgenerated, Fragment Generator C21020 may generate the fragment headercorresponding to the fragment payload.

Transmission Block Generator C21030 may generate at least one TBindicating a data unit that is encoded and transmitted through fragmentsegmentation.

The transmission block (TB) according to the embodiment may indicate aminimum data unit that is independently encoded and transmitted withoutdepending on the preceding data. For example, the TB may include one ormore chunks composed of the same media data as in GOP of video data.

Transmission Block Generator C21030 may first transmit the TBcorresponding to the fragment payload, and may generate the TBcorresponding to the fragment header.

Transmission Block Generator C21030 may generate as a single TB.However, the scope or spirit of the present invention is not limitedthereto, and the Transmission Block Generator C21030 may generate thefragment header as one or more TBs.

For example, if Fragment Generator C21020 generates the fragment payloadconstructing each fragment and then generates the fragment header, theTransmission Block Generator C21030 generates the transmission block(TB) corresponding to the fragment payload and then generates the TBcorresponding to the fragment header.

However, the scope or spirit of the present invention is not limitedthereto. If the fragment header and the fragment payload for themultimedia content are generated, the TB corresponding to the fragmentheader may be first generated and the TB corresponding to the fragmentpayload may be generated.

Transmission Block Generator C21030 may generate a transmission block(TB) corresponding to the fragment payload and a TB corresponding to thefragment header as different TBs.

Packetizer C21040 may divide the TB into one or more equal-sizedsymbols, so that the one or more symbols may be packetized into at leastone packet. However, the scope or spirit of the present invention is notlimited thereto, and the symbols may also be generated by other devices.In accordance with the embodiment, the symbols may have the same length.However, the last symbol of each TB may be less in length than othersymbols.

Thereafter, Packetizer C21040 may packetize at least one symbol into oneor more packets. For example, the packet may be an LCT packet. Thepacket may include a packet header and a packet payload.

The packet header may include fragment information having specificinformation regarding file segmentation generation and segmentationconsumption. The file segmentation generation may indicate that data isdivided into at least one chunk or at least one TB capable ofindependently encoding/transmitting the file constructing the multimediacontent. The file segmentation consumption may indicate that at leastone fragment capable of performing independent decoding/reproducing bycombination of at least one TB is recovered and is reproduced on afragment basis. In addition, segmentation consumption of the file mayinclude data that is reproduced on a TB basis.

For example, the fragment information may include at least one of an SIfield indicating that a packet includes initial data of the fragment, anFH field indicating that a packet includes header data, fragmentcompletion information indicating that generation of a TB correspondingto each fragment is completed, and a PB field indicating the number ofpadding bytes contained in a packet.

The fragment information may further include a Header Extension Type(HET) field indicating the type of a Header Extension of thecorresponding packet.

The fragment completion information may include at least one of the FCfield indicating that a packet includes the last data of the fragmentheader and the FHL field indicating a total number of symbolscorresponding to the fragment header.

The fragment information may be generated by Packetizer C21040, and maybe generated by a separate device. The following description willhereinafter described on the basis of an exemplary case in which thepacketizer C21040 generates the fragment information.

Packetizer C21040 may identify whether the generated symbol includesfirst data of the fragment.

For example, the packetizer C21040 may identify whether the generatedsymbol has first data of the fragment payload. If the generated symbolhas first data of the fragment payload, the SI field may be set to 1. Ifthe generated symbol does not have first data of the fragment payload,the SI field may be set to zero ‘0’.

Packetizer C21040 may identify whether the generated symbol has data ofthe fragment payload or data of the fragment header.

For example, if the generated symbol has data of the fragment payload,the FH field may be set to 1. If the generated symbol does not have dataof the fragment payload, the FH field may be set to zero ‘0’.

Packetizer C21040 may identify whether generation of a TB correspondingto each fragment is completed. If fragment completion informationindicating generation completion of a TB corresponding to each fragmentmay include the FC field indicating inclusion of the last data of thefragment header.

For example, if the generated symbol has data of the fragment header andis the last symbol of the corresponding TB, the FC field may be setto 1. If the generated symbol does not have data of the fragment headeris not identical to the last symbol of the corresponding TB, the FCfield may be set to zero ‘0’.

Packetizer C21040 may identify whether the generated symbol is the lastsymbol of the corresponding TB and has a length different from that ofanother symbol. For example, another symbol may be a symbol having apredetermined length, and the symbol having a different length fromother symbols may be shorter in length than other symbols.

For example, if the generated symbol is the last symbol of thecorresponding TB and has a different length from other symbols, thepacketizer C21040 may insert the padding bytes into a packetcorresponding to the last symbol of each TB. The packetizer C21040 maycalculate the number of padding bytes.

In addition, the PB field may indicate the number of padding bytes. Thepadding byte is added to each symbol having a shorter length than othersymbols in such a manner that all symbols may have the same length.Alternatively, the padding bytes may be the remaining parts other thansymbols of the packet.

If the generated symbol is not identical to the last symbol of thecorresponding TB or has a different length from other symbols, the PBfield may be set to zero ‘0’.

The packet payload may include at least one symbol. The followingdescription will hereinafter disclose an exemplary case in which onepacket includes one symbol.

The packet having the last symbol of each TB may include at least onepadding byte.

Transmitter C21050 may transmit one or more packet in the order of TBgeneration.

For example, the transmitter C21050 may first transmit the TBcorresponding to the fragment payload, and then transmit the TBcorresponding to the fragment header.

However, the scope or spirit of the present invention is not limitedthereto. If the fragment header and the fragment payload arepre-generated for multimedia content, the transmitter C21050 accordingto the embodiment may first transmit the TB corresponding to thefragment header, and then transmit the TB corresponding to the fragmentpayload.

FIG. 35 is a flowchart illustrating a process for generating andtransmitting in real time the file-based multimedia content according toan embodiment of the present invention.

FIG. 35 is a flowchart illustrating a method for transmitting broadcastsignals using the above-mentioned broadcast signal transmissionapparatus shown in FIG. 34.

Referring to FIG. 35, the broadcast signal transmission apparatusaccording to the embodiment may encode multimedia content using theMedia Encoder C21010 in step CS11100. The broadcast signal transmissionapparatus may encode multimedia content and then generate media data.

Thereafter; the broadcast signal transmission apparatus may performbuffering of media data corresponding to the fragment payload in stepCS11200. The broadcast signal transmission apparatus may generate achunk corresponding to the fragment payload on the basis of the bufferedmedia data.

If generation of the chunk corresponding to the fragment payload is notcompleted, the broadcast signal transmission apparatus continuouslyperform buffering of media data, and then completes generation of thechunk corresponding to the fragment payload in step CS11300.

Thereafter, the broadcast signal transmission apparatus may divide eachfile constructing the multimedia content using the fragment generatorC21020, such that it may generate at least one fragment indicating adata unit that is independently decoded and reproduced in step CS11400.

The broadcast signal transmission apparatus may generate the fragmentpayload constructing each fragment, and then generate the fragmentheader.

The broadcast signal transmission apparatus may determine whether alldata corresponding to the fragment payload is generated as a chunkwhenever the chunk is generated.

If generation of the chunk corresponding to the fragment payload iscompleted, the broadcast signal transmission apparatus may generate thefragment header corresponding to the fragment payload.

The broadcast signal transmission apparatus divides the fragment usingthe transmission block generator C21030, so that it can generate atleast one TB indicating a data unit that is independently encoded andtransmitted in step CS11500.

For example, when the fragment header is generated after the fragmentpayload constructing each fragment has been generated, the broadcastsignal transmission apparatus may generate the TB corresponding to thefragment payload and then generate the TB corresponding to the fragmentheader.

The broadcast signal transmission apparatus may generate a TBcorresponding to the fragment payload and a TB corresponding to thefragment header as different TBs.

Thereafter, the broadcast signal transmission apparatus may divide theTB into one or more equal-sized symbols using the packetizer C21040, andmay packetize at least one symbol into at least one packet in stepsCS11600 and CS11700.

A method for generating a packet using the broadcast signal transmissionapparatus has already been disclosed in FIG. 35, and as such a detaileddescription thereof will herein be omitted for convenience ofdescription.

Thereafter, the broadcast signal transmission apparatus may control thetransmitter C21050 to transmit one or more packets in the order of TBgeneration.

FIG. 36 is a flowchart illustrating a process for allowing the broadcastsignal transmission apparatus to generate packets using a packetizeraccording to an embodiment of the present invention.

Referring to FIG. 36, the broadcast signal transmission apparatus mayidentify whether the generated symbol has first data of the fragment instep CS11710.

For example, if the generated symbol has first data of the fragmentpayload, the SI field may be set to 1 in step CS11712. If the generatedsymbol does not include first data of the fragment payload, the SI fieldmay be set to zero ‘0’ in step CS11714.

Thereafter, the broadcast signal transmission apparatus may identifywhether the generated symbol has data of the fragment payload or data ofthe fragment header in step CS11720.

For example, if the generated symbol has data of the fragment payload,the FH field may be set to 1 in step CS11722. If the generated symboldoes not have data of the fragment payload, the FH field may be set tozero ‘0’ in step CS11724.

The broadcast signal transmission apparatus may identify whethergeneration of the TB corresponding to each fragment is completed in stepCS11730.

For example, if the generated symbol has data of the fragment header andis the last symbol of the corresponding TB, the FC field may be set to 1in step CS11732. If the generated symbol does not have data of thefragment header or is not identical to the last symbol of thecorresponding TB, the FC field may be set to zero ‘0’ in step CS11734.

Thereafter, the broadcast signal transmission apparatus may identifywhether the generated symbol is the last symbol of the corresponding TBand has a different length from other symbols in step CS11740.

For example, if the generated symbol is the last symbol of thecorresponding TB and has a different length from other symbols, thebroadcast signal transmission apparatus may insert the padding bytesinto a packet corresponding to the last symbol of each TB. The broadcastsignal transmission apparatus may calculate the number of padding bytesin step CS11742. The PB field may indicate the number of padding bytes.

If the generated symbol is not identical to the last symbol of thecorresponding TB or has a different length from other symbols, the PBfield may be set to zero ‘0’ in step CS11744.

The packet payload may include at least one symbol.

FIG. 37 is a flowchart illustrating a process forgenerating/transmitting in real time the file-based multimedia contentaccording to another embodiment of the present invention.

Referring to FIG. 37, contents shown in FIGS. 35 and 36 from among allcontents of FIG. 37 are substantially identical to each other, and assuch a detailed description thereof will herein be omitted forconvenience of description.

In accordance with another embodiment, the broadcast signal transmissionapparatus may use the FHL field instead of the FC field. For example,the above-mentioned fragment information may include fragment completioninformation indicating generation completion of a TB corresponding toeach fragment. The fragment completion information may include the FHLfield indicating a total number of symbols corresponding to the fragmentheader.

The broadcast signal transmission apparatus according to the embodimentmay calculate the number of symbols corresponding to the TB includingdata of the fragment header, and may record the calculated result in theFHL field in step CS12724.

The FHL field may indicate the length of a fragment header as a totalnumber of symbols corresponding to the fragment header. The FHL fieldmay be contained in the fragment information instead of theabove-mentioned FC field in such a manner that the broadcast signalreception apparatus can identify reception completion of the fragmentheader.

The broadcast signal reception apparatus according to the embodimentchecks the number of transmission times of a packet including as manyfragment headers as the number of data pieces recorded in the FHL field,so that it can identify whether or not the fragment header is received.

FIG. 38 is a block diagram illustrating a file-based multimedia contentreceiver according to an embodiment of the present invention.

Referring to FIG. 38, the broadcast signal reception apparatus fortransmitting a broadcast signal including multimedia content using thebroadcast network may include a receiver (not shown), a signalingdecoder 22005, a Transmission Block Regenerator C22030, and/or a MediaDecoder C22060.

The signaling decoder C22005 may decode signaling information. Thesignaling information may indicate whether the multimedia content willbe transmitted in real time.

If the signaling information indicates real-time transmission of themultimedia content, Transmission Block Regenerator C22030 combinesbroadcast signals, so that it can recover at least one TB indicating adata unit that is independently encoded and transmitted.

Media Decoder C22060 may decode the TB.

A detailed description thereof will hereinafter be described withreference to FIG. 39.

FIG. 39 is a block diagram illustrating a file-based multimedia contentreceiver according to an embodiment of the present invention.

Referring to FIG. 39, the broadcast signal reception apparatus accordingto the embodiment may include a receiver (not shown), a signalingdecoder (not shown), a Packet Filter C22010, a Packet DepacketizerC22020, a Transmission Block Regenerator C22030, a Fragment RegeneratorC22040, a Fragment Parser C22050, a Media Decoder C22060, and/or a MediaRenderer C22070.

The receiver (not shown) may receive a broadcast signal. The broadcastsignal may include at least one packet. Each packet may include a packetheader including fragment information and a packet payload including atleast one symbol.

The signaling decoder C22005 may decode signaling information. Thesignaling information may indicate whether the multimedia content willbe transmitted in real time. Packet Filter C22010 may identify afragment start time starting from at least one packet received at anarbitrary time, and may start packet processing from the fragment starttime.

Packet Filter C22010 may identify the fragment start time on the basisof the SI field of fragment information contained in the packet.

If Packet Filter C22010 indicates that the corresponding packet includesa start part of the fragment, the previous packets of the correspondingpacket are discarded and some packets starting from the correspondingpacket may be transmitted to the packet depacketizer C22020.

For example, the packet filter C22010 discards the previous packets,each of which is set to 1, and some packet starting from thecorresponding packet that is set to 1 may be filtered.

The packet depacketizer C22020 may depacketize at least one packet, andmay extract fragment information contained in the fragment header and atleast one symbol contained in the packet payload.

Transmission Block Regenerator C22030 may combine packets so that it canrecover at least one TB indicating a data unit that is independentlyencoded and transmitted. The recovered TB may include data correspondingto the fragment header, and may include data corresponding to thefragment payload.

Fragment Regenerator C22040 combines at least one TB, completes recoveryof the fragment header and the fragment payload, and combines thefragment header and the fragment payload, so that the fragmentregenerator C22040 may recover the fragment indicating a data unit thatis independently decoded and reproduced.

Fragment Regenerator C22040 combines the TB on the basis of fragmentinformation, so that the fragment regenerator C22040 may recover thefragment payload and the fragment header.

Fragment Regenerator C22040 may first recover the fragment payload inthe order of reception packets, and may recover the fragment header. Ifthe FH field indicates that the packet has data of the fragment header,the fragment regenerator C22040 may combine at least one TBcorresponding to the fragment header so that it recovers the fragmentheader according to the combined result.

If the FH field indicates that the packet does not include data of thefragment header, the Fragment Regenerator C22040 may recover thefragment payload by combining at least one TB.

For example, if the FH field is set to zero ‘0’, the FragmentRegenerator C22040 may determine fragment payload so that it can recoverthe fragment payload. If the FH field is set to 1, the fragmentregenerator C22040 determines the fragment header so that it can recoverthe fragment header.

Thereafter, if Fragment Regenerator C22040 completes recovery of thefragment payload and the fragment header corresponding to each fragment,the recovered fragment payload and the recovered fragment header arecombined so that the fragment is recovered.

There are two methods for allowing the fragment regenerator C22040 todetermine whether recovery of the fragment payload and the fragmentheader corresponding to each fragment has been completed.

The first method is to use the FC field contained in the fragmentinformation.

The fragment completion information may include the FC field indicatingthat the packet has the last data of the fragment header. If the FCfield indicates that the packet has the last data of the fragmentheader, the Fragment Regenerator C22040 determines that the fragmentheader constructing each fragment and the fragment payload have beenreceived, and can recover the fragment header and the fragment payload.

For example, if the fragment payload constructing each fragment is firstreceived and the fragment header is then received, the FC field mayindicate that the corresponding packet includes the last data of thefragment header.

Therefore, if the FC field indicates that the corresponding packet hasthe last data of the fragment header, the Fragment Regenerator C22040may recognize reception completion of the fragment header and mayrecover the fragment header. Thereafter, the Fragment Regenerator C22040may combine the fragment header and the fragment payload so as torecover the fragment.

If the FC field indicates that the corresponding packet has the lastdata of the fragment header, the broadcast signal reception apparatusmay repeat a process for recovering the transmission block (TB).

For example, if the FC field is not set to 1, the broadcast signalreception apparatus may repeat the recovery process of the TB. If the FCfield is set to 1, the Fragment Regenerator C22040 may recover thefragment by combination of the fragment header and the fragment payload.

The second method can determine whether recovery of the fragment payloadconstructing each fragment and the fragment header has been completed onthe basis of the FHL field contained in the fragment information.

The Fragment Regenerator C22040 may count the number of packetsincluding data of the fragment header.

The fragment completion information may further include the FHL fieldindicating a total number of symbols corresponding to the fragmentheader. If the value recorded in the FHL field is identical to thenumber of packets having data of the fragment header, the FragmentRegenerator C22040 may recover the fragment header and the fragmentpayload.

A detailed description of a method for allowing the fragment regeneratorC22040 to use the FHL field is shown in FIG. 39.

Fragment Parser C22050 may parse the recovered fragment. Since thefragment header is located at the front of the recovered fragment andthe fragment payload is located at the rear of the recovered fragment,the Fragment Parser C22050 may first parse the fragment header and thenparse the fragment payload.

Fragment Parser C22050 may parse the recovered fragment so that it cangenerate at least one media access unit. For example, the media accessunit may include at least one media data. The media access unit may havea unit of media data having a predetermined size.

Media Decoder C22060 may decode the fragment. Media Decoder C22060 maydecode at least one media access unit so as to generate media data.

Media Renderer C22070 may render the decoded media data so as to performpresentation.

FIG. 40 is a flowchart illustrating a process for receiving/consuming afile-based multimedia content according to an embodiment of the presentinvention.

Contents shown in FIG. 39 can be equally applied to the broadcast signalreception method according to the embodiment.

Referring to FIG. 40, a broadcast signal reception method for receivingmultimedia content including at least one file includes: receiving themultimedia content divided into at least one packet; recovering at leastone TB indicating a data unit that is independently encoded andtransmitted by packet combination; and completing recovery of thefragment header and the fragment payload by combination of one or moreTBs, recovering a fragment indicating a data unit that is independentlyencoded and reproduced by combination of the fragment header and thefragment payload, and/or performing fragment decoding.

The broadcast signal reception apparatus according to the embodiment mayreceive a broadcast signal using the receiver (not shown) in stepS21010. The broadcast signal may include at least one packet.

Thereafter, the broadcast signal reception apparatus according to theembodiment may control the packet filter C22010 to identify a fragmentstart time from at least one packet received at an arbitrary time instep CS21020.

Thereafter, the broadcast signal reception apparatus according to theembodiment may depacketize at least one packet using the packetdepacketizer C22020, so that it can extract at least one symbolcontained in the fragment information and packet payload contained inthe packet header in step CS21030.

Thereafter, the broadcast signal reception apparatus combines packetsusing the transmission block regenerator C22030, so that it can recoverat least one TB indicating a data unit that is independently encoded andtransmitted in step CS21040. The reproduced TB may include datacorresponding to the fragment header, and may include data correspondingto the fragment payload.

The broadcast signal reception apparatus according to the embodiment maycontrol the fragment regenerator C22040 to identify whether the TBreproduced on the basis of fragment information is a TB corresponding tothe fragment header and a TB corresponding to the fragment payload instep CS21050.

Thereafter, the broadcast signal reception apparatus may combine therecovered TB so that it can recover the fragment payload and thefragment header.

If the FH field indicates that the packet does not include data of thefragment header, the broadcast signal reception apparatus combines atleast one TB corresponding to the fragment payload so that it canrecover the fragment payload in step CS21060.

If the FH field indicates that the packet has data of the fragmentheader, the broadcast signal reception apparatus may recover thefragment header by combination of at least one TB corresponding to thefragment header in step CS21070.

The broadcast signal reception apparatus may determine whether thefragment payload constructing each fragment and the fragment header onthe basis of the FC field contained in fragment information have beencompletely recovered in step CS21080.

If the FC field indicates, that the corresponding packet does not havethe last data of the fragment header, the broadcast signal receptionapparatus may repeat the TB recovery process.

If the FC field indicates that the corresponding packet has the lastdata of the fragment, the broadcast signal reception apparatus maydetermine reception completion of each fragment.

For example, if the fragment header is received after the fragmentpayload constructing each fragment is first received, the FC field mayindicate that the corresponding packet has the last data of the fragmentheader.

Therefore, if the FC field indicates that the packet has the last dataof the fragment header, the broadcast signal reception apparatusdetermines that the fragment header constructing each fragment and thefragment payload have been completely received, so that it can recoverthe fragment header and the fragment payload.

If the FC field indicates that the corresponding packet does not havethe last data of the fragment header, the broadcast signal receptionapparatus may repeat the TB recovery process.

Thereafter, the broadcast signal reception apparatus may combine atleast one TB using the Fragment Regenerator C22040 to complete recoveryof the fragment header and the fragment payload, and may combine thefragment header and the fragment payload to recover the fragmentindicating a data unit that is independently decoded and reproduced instep CS21090.

The broadcast signal reception apparatus according to the embodiment mayparse the recovered fragment using the fragment parser C22050 in stepCS21090. The broadcast signal reception apparatus parses the recoveredfragment so that it can generate at least one media access unit.However, the scope or spirit of the present invention is not limitedthereto, and the broadcast signal reception apparatus parses the TB sothat it can generate at least one media access unit.

Thereafter, the broadcast signal reception apparatus according to theembodiment may decode at least one media access unit using the mediadecoder C22060, so that it can generate media data in step CS21100.

The broadcast signal reception apparatus according to the embodiment mayperform rendering of the decoded media data using the media rendererC22070 so as to perform presentation in step CS21110.

FIG. 41 is a flowchart illustrating a process for receiving/consuming inreal time a file-based multimedia content according to anotherembodiment of the present invention.

Referring to FIG. 41, some parts of FIG. 41 are substantially identicalto those of FIG. 40, and as such a detailed description thereof willherein be omitted.

The broadcast signal reception apparatus according to the embodiment maydetermine whether the fragment header and the fragment payloadconstructing each fragment have been completely received on the basis ofthe FHL field.

The broadcast signal reception apparatus according to the embodiment mayallow the fragment regenerator C22040 to identify whether the TBrecovered on the basis of fragment information is a TB corresponding tothe fragment header or a TB corresponding to the fragment payload instep CS22050.

Thereafter, the broadcast signal reception apparatus combines therecovered TBs so that it can recover each of the fragment payload andthe fragment header.

If the FH field indicates that the corresponding packet has datacorresponding to the fragment payload, the broadcast signal receptionapparatus may combine at least one TB so that it can recover thefragment payload in step CS22060.

If the FH field indicates that the corresponding packet has datacorresponding to the fragment header, the Fragment Regenerator C22040may recover the fragment header by combination of at least one TB instep CS22070.

Thereafter, if the broadcast signal reception apparatus completesrecovery of the fragment payload constructing each fragment and thefragment header, the fragment signal reception apparatus may recover thefragment by combination of the recovered fragment payload and thefragment header.

The broadcast signal reception apparatus may determine whether thefragment payload constructing each fragment and the fragment header havebeen completely reproduced on the basis of the FHL field contained infragment information.

The broadcast signal reception apparatus may count the number (N) ofpackets constructing each fragment in step CS22080. For example, thebroadcast signal reception apparatus may count the number of packetseach having data of the fragment header. One packet may include at leastone symbol, and the following description will hereinafter describe anexemplary case in which one packet includes one symbol.

The FHL field may indicate the number of symbols constructing thefragment. If as many packets as the number of symbols recorded in theFHL field are not received, the broadcast signal reception apparatus mayrepeat the TB recovery process. For example, if reception of thefragment payload constructing each fragment and the fragment header isnot completed, the broadcast signal reception apparatus may repeat theTB recovery process.

Fragment completion information may further include the FHL fieldindicating a total number of symbols corresponding to the fragmentheader.

If the value recorded in the FHL field is identical to the number ofpackets, the broadcast signal reception apparatus determines that thefragment payload constructing each fragment and the fragment header havebeen completely received, and then recovers the fragment header and thefragment payload in step CS22090.

For example, the FHL field may indicate a total number of symbolscorresponding to each fragment including both the fragment header andthe fragment payload. In this case, if as many packets as the number ofsymbols recorded in the FHL field are received, the broadcast signalreception apparatus can determine that the fragment payload constructingeach fragment and the fragment header have been completely received.

For example, the FHL field may indicate a total number of symbols to betransmitted later from among the fragment header and the fragmentpayload.

If the fragment payload constructing each fragment is first received andthe fragment header is then received, the FHL field may indicate a totalnumber of symbols corresponding to the fragment header. In this case,the number of symbols recorded in the FHL field is identical to thenumber of packets corresponding to the received fragment header, thebroadcast signal reception apparatus may determine that the fragmentpayload constructing each fragment and the fragment header have beencompletely received.

In addition, if the fragment header constructing each fragment is firstreceived and the fragment payload is then received, the FHL field mayindicate a total number of symbols corresponding to the fragmentpayload. In this case, if the number of symbols recorded in the FHLfield is identical to the number of packets corresponding to thereceived fragment payload, the broadcast signal reception apparatus maydetermine that the fragment payload constructing each fragment and thefragment header have been completely received.

Thereafter, if the fragment payload constructing each fragment and thefragment header have been completely received, the broadcast signalreception apparatus combines the fragment header and the fragmentpayload so as to recover the fragment in step CS22100.

Thus far, an embodiment of the present invention in which multimediacontent is transmitted and received through a broadcast network in atransport block unit in real time using a transport block as a data unitwith a variable size has been described.

Hereinafter, another embodiment of the present invention in whichmultimedia content is transmitted and received through a broadcastnetwork in an object internal structure unit with a variable size inreal time using boundary information and type information of the objectinternal structure will be described.

However, the same terms of another embodiment of the present inventionas in an embodiment of the present invention may include the abovedescription, and thus a detailed description thereof will be omittedherein. In addition, the descriptions related to FIGS. 1 to 41 can alsobe applied to FIGS. 42 to 55.

<Identifying Method of Transport Object Type-1>

FIG. 42 is a diagram illustrating a structure of a packet includingobject type information according to another embodiment of the presentinvention.

According to another embodiment of the present invention, a packet maybe an LCT packet and the LCT packet may include an LCT version numberfield (V), a congestion control flag field (C), a protocol-specificindication field (PSI), a transport session identifier flag field (S), atransport object identifier flag field (O), a half-word flag field (H),a sender current time present flag field (T), an expected residual timepresent flag field (R), a close session flag field (A), a close objectflag field (B), an LCT header length field (HDR_LEN), a codepoint field(CP), a congestion control information field (CCI), a transport sessionidentifier field (TSI), a transport object identifier field (TOI), aheader extensions field, an FEC Payload ID field, and/or an encodingsymbol(s) field.

According to another embodiment of the present invention, a packet mayinclude packet information including metadata. The packet informationmay include object type information indicating a type of an object thatis transmitted by the current packet during transmission of MPEG-DASHcontent. The object type information may indicate a type of an objectthat is transmitted in a current packet or packets to which the same TOIis applied.

For example, the object type information may identify an object typeusing two reserved bits positioned at a 12th bit from a start point ofan LCT packet.

When MPEG-DASH content is transmitted in an LCT packet, the object typemay include a regular file, initialization segment, media segment,and/or self-initializing segment.

For example, when a value of the object type information is “00”, theobject type may indicate “regular file”, when a value of the object typeinformation is “01”, the object type may indicate “initializationsegment”, when a value of the object type information is “10”, theobject type may indicate “media segment”, and a value of the object typeinformation is “11”, the object type may indicate “self-initializingsegment”.

An object type indicated by object type information may be variedaccording to transmitted file content and a scheme for defining a valueof object type information may be transmitted in the form of signalinginformation separately from a session for current transmission orout-of-band.

The regular file refers to a data unit of the object form such as aregular file constituting multimedia content.

The initialization segment refers to a data unit of the object formincluding initialization information for access to representation.Initialization Segment may include a file type box (ftyp) and a moviebox (moov). The file type box (ftyp) may include a file type, a fileversion, and compatibility information. The movie box (moov) may includemetadata for describing media content.

The media segment refers to a data unit of the object form associatedwith media divided according to quality and time, which is to betransmitted to a broadcast signal receiving apparatus in order tosupport a streaming service. The media segment may include a segmenttype box (styp), a segment index box (sidx), a movie fragment box(moof), and a media data box (mdat). The segment type box (styp) mayinclude segment type information. The segment index box (sidx) mayprovide stream access points (SAP) information, data offset, initialpresentation time of media data present in the corresponding mediasegment, etc. The movie fragment box (moof) may include metadata aboutmedia data box (mdat). The media data box (mdat) may include actualmedia data about a component media component (video, audio, etc.).

The self-initializing segment refers to a data unit of the object formincluding both information of initialization segment and information ofmedia segment.

<Identifying Method of Transport Object Type-2>

FIG. 43 is a diagram illustrating a structure of a packet includingobject type information according to another embodiment of the presentinvention.

In addition to the aforementioned method, the object type informationcan identify a type of an object that is transmitted in a current packetusing LCT header extension. The object type information using LCT headerextension can be applied to a packet, etc. for a transport protocol suchas a realtime protocol (RTP), etc.

The object type information may include a header extension type (HET)field, a type field, and/or a reserved field.

The HET field may be an 8-bit integer and may indicate a type of thecorresponding header extension. For example, the HET field may be onecharacteristic value among values of 128 to 255 and may identify a typeof the corresponding header extension. In this case, the headerextension may have a fixed length of 32 bits.

The type field may indicate a type of an object that is transmitted in acurrent LCT packet or packets to which the same TOI is applied.Hereinafter, the type field may be represented by object typeinformation. When MPEG-DASH content is transmitted in the LCT packet,the object type may include the regular file, initialization segment,media segment, and self-initializing segment according to a value of theobject type information.

For example, when a value of the object type information is “0x00”, theobject type may indicate “regular file”, when a value of the object typeinformation is “0x01”, the object type may indicate “initializationsegment”, when a value of the object type information is “0x10”, theobject type may indicate “media segment”, and when a value of the objecttype information is “0x11”, the object type may indicate“self-initializing segment”.

The reserved field is reserved for future use.

Hereinafter, a detailed description for FIG. 43 is the same as in theabove detailed description, and thus will be omitted herein.

FIG. 44 is a diagram illustrating a structure of a broadcast signalreceiving apparatus using object type information according to anotherembodiment of the present invention.

The broadcast signal receiving apparatus may different procedures basedon the object type information according to an object type. That is,upon specifying and transmitting object type information in an LCTpacket, the broadcast signal receiving apparatus may identify an objectreceived based on the object type information and perform an appropriateoperation according to an object type.

A broadcast signal receiving apparatus according to another embodimentof the present invention may include a signaling decoder C32005, aparser C32050, and/or a decoder C32060. However, components of thebroadcast signal receiving apparatus are not limited thereto and theaforementioned components may be further included.

The signaling decoder C32005 may decode signaling information. Thesignaling information indicates whether a broadcast signal includingmultimedia content is transmitted using a broadcast network in realtime.

The parser C32050 may parse at least one object based on the object typeinformation and generate initialization information for access toRepresentation and at least one access unit. To this end, the parserC32050 may include an initialization segment parser C32051, a mediasegment parser C32052, and/or a self-initializing segment parser C32053.The initialization segment parser C32051, the media segment parserC32052, and the self-initializing segment parser C32053 will bedescribed in detail in the next diagrams.

The decoder C32060 may initialize the corresponding decoder C32060 basedon the initialization information. In addition, the decoder C32060 maydecode at least one object. In this case, the decoder C32060 may receiveinformation about an object in the form of at least one access unit anddecode at least one access unit to generate media data.

FIG. 45 is a diagram illustrating a structure of a broadcast signalreceiving apparatus using object type information according to anotherembodiment of the present invention.

The broadcast signal receiving apparatus may include a packet filterC32010, a segment buffer C32030, the parser C32050, a decoding bufferC32059, and/or the decoder C32060.

The packet filter C32010 may identify the object type information fromat least one received packet and classify the object type information soas to perform a procedure corresponding to each object type based on theobject type information.

For example, when the object type information is “1”, the packet filterC32010 may transmit data of an LCT packet to the initialization segmentparser C32051 through a segment buffer C32031, when the object typeinformation is “2”, the packet filter C32010 may transmit data of an LCTpacket to the media segment parser C32052 through a segment bufferC32032, when the object type information is “3”, the packet filterC32010 may transmit data of an LCT packet to the self-initializingsegment parser C32053 through a segment buffer C32033.

The segment buffer C32030 may receive data of an LCT packet from apacket filter and store the data for a predetermined period of time. Thesegment buffer C32030 may be present as one component or a plurality ofsegment buffers C32031, C32032, and C32033.

The parser C32050 may parse at least one object based on the object typeinformation and generate initialization information for access torepresentation and at least one access unit. To this end, the parserC32050 may include the initialization segment parser C32051, the mediasegment parser C32052, and/or the self-initializing segment parserC32053.

The initialization segment parser C32051 may parse initializationsegment stored in the segment buffer C32031 and generate initializationinformation for access to representation.

In addition, the initialization segment parser C32051 may receiveinitialization segment from the self-initializing segment parser C32053and generate initialization information for access to representation.The media segment parser C32052 may parse media segment stored in thesegment buffer C32032 and generate information about media stream, atleast one access unit, and information about a method for access tomedia presentation in the corresponding segment, such as presentationtime or Index. In addition, the media segment parser C32052 may receivemedia segment from the self-initializing segment parser c32053 andgenerate information of media stream, at least one access unit, andinformation about a method for access to media presentation in thecorresponding segment, such as presentation time or index.

The self-initializing segment parser C32053 may parse self-initializingsegment stored in the segment buffer c32033 and generate initializationsegment and media segment.

The decoding buffer C32059 may receive at least one access unit from theparser C32050 or the media segment parser C32052 and store the accessunit for a predetermined period of time.

The decoder C32060 may initialize the corresponding decoder C32060 basedon the initialization information. In addition, the decoder C32060 maydecode at least one object. In this case, the decoder C32060 may receiveinformation about an object in the form of at least one access unit andmay decode at least one access unit to generate media data.

As described above, upon transmitting MPEG-DASH content, a broadcastsignal transmitting apparatus according to another embodiment of thepresent invention may transmit object type information indicating a typeof an object that is transmitted in a current packet. In addition, thebroadcast signal transmitting apparatus may identify a type of an objectin a packet received based on the object type information and perform anappropriate process on each object.

<Type of Object Internal Structure>

FIG. 46 is a diagram illustrating a structure of a packet including typeinformation according to another embodiment of the present invention.

Upon transmitting data in an object internal structure unit as anindependently meaningful unit, a broadcast signal transmitting apparatusmay transmit data with a variable size. Thus, upon receiving andidentifying an object internal structure even prior to receiving oneentire object, a broadcast signal receiving apparatus may performreproduction in an object internal structure unit. As a result,multimedia content may be transmitted and reproduced through a broadcastnetwork in real time. According to another embodiment of the presentinvention, in order to identify an object internal structure, Typeinformation and Boundary Information may be used.

Hereinafter, type information for identification of an object internalstructure will be described in detail.

During transmission of MPEG-DASH content, packet information may includetype information using LCT header extension. The type information mayindicate a type of an object internal structure that is transmitted in acurrent packet. The type information may be referred to as internalstructure type information for differentiation from object typeinformation. The type information can be applied to a packet, etc. for atransport protocol such as realtime protocol (RTP), etc.

The type information may include a header extension type field (HET), aninternal unit type field, and/or a reserved field.

The HET field is the same as in the above description and thus adetailed description thereof is omitted herein.

The internal structure type field may indicate a type of an objectinternal structure transmitted in an LCT packet.

An object may correspond to a segment of MPEG-DASH and an objectinternal structure may correspond to a lower component included in theobject. For example, a type of the object internal structure may includefragment, chunk or GOP, an access unit, and a NAL unit. The type of theobject internal structure may not be limited thereto and may furtherinclude meaningful units.

The fragment refers to a data unit that can be independently decoded andreproduced without dependence upon preceding data. Alternatively, thefragment may refer to a data unit including one pair of movie fragmentbox (moot) and media data container box (mdat). For example, thefragment may correspond to subsegment of MPEGDASH or correspond to afragment of MMT. The fragment may include at least one chunk or at leastone GOP.

The chunk is a set of adjacent samples with the same media type and is adata unit with a variable size.

GOP is a basic unit for performing coding used in video coding and is adata unit with a variable size indicating a set of frames including atleast one I-frame. According to another embodiment of the presentinvention, media data is transmitted in an object internal structureunit as an independently meaningful data unit, and thus GOP may includeOpen GOP and Closed GOP.

In Open GOP, B-frame in one GOP may refer to I-frame or P-frame of anadjacent GOP. Thus, Open GOP can seriously enhance coding efficiency. InClosed GOP, Bframe or P-frame may refer to only a frame in thecorresponding GOP and may not refer to frames in GOPs except for thecorresponding GOP.

The access unit may refer a basic data unit of encoded video or audioand include one image frame or audio frame.

The NAL unit is an encapsulated and compressed video stream includingsummary information, etc. about a slice compressed in consideration ofcommunication with a network device. For example, the NAL unit is a dataunit obtained by packetizing data such as a NAL unit slice, a parameterset, SEI, etc. in a byte unit.

The reserved field may be reserved for future use.

Hereinafter, for convenience of description, the internal structure typefield may be represented by type information.

<Boundary of Object Internal Structure>

FIG. 47 is a diagram illustrating a structure of a packet includingboundary information according to another embodiment of the presentinvention.

Hereinafter, boundary information for identification of an objectinternal structure will be described in detail.

During transmission of MPEG-DASH content, packet information may includeboundary information using LCT header extension. The boundaryinformation may indicate a boundary of an object internal structure thatis transmitted in a current packet. The boundary information can beapplied to a packet, etc. for a transport protocol such as a realtimeprotocol (RTP), etc.

The boundary information may include a header extension type field(HET), a start flag field (SF), a reserved field, and/or an offsetfield.

The HET field is the same as in the above description and thus is notdescribed in detail.

The start flag field (SF) may indicate that an LCT packet includes astart point of an object internal structure.

The reserved field may be reserved for future use.

The offset field may include position information indicating a startpoint of the object internal structure in an LCT packet. The positioninformation may include a byte distance to the start point of the objectinternal structure from a payload start point of the LCT packet.

As described above, a broadcast signal transmitting apparatus may nottransmit data in object units based on type information and boundaryinformation and may transmit data in an object internal structure unitwith a variable length.

A broadcast signal receiving apparatus may not receive and reproducedata in object units and may receive and reproduce data in an objectinternal structure unit with a variable length. Thus, the broadcastsignal receiving apparatus may identify the object internal structurebased on type information and boundary information and performreproduction for each received object internal structure.

For example, the broadcast signal receiving apparatus may identify atype of a current object internal structure based on packetscorresponding to start and end points of the object internal structurerepresented by the boundary information or type information included inat least one packet transmitted between the start and end points.

As a result, the broadcast signal receiving apparatus may rapidlyidentify the object internal structure and perform reproduction in realtime even prior to receiving one entire object.

<Mapping of Transport Object and Signaling Information>

FIG. 48 is a diagram illustrating a structure of a packet includingmapping information according to another embodiment of the presentinvention.

According to another embodiment of the present invention, an objectinternal structure can be identified using mapping information inaddition to the aforementioned type information and boundaryinformation.

During transmission of DASH content, the packet information may includethe mapping information using LCT header extension. The mappinginformation maps at least one of a session transmitted in a currentpacket, an object and an object internal structure to at least one of atransport session identifier (TSI) and a transport object identifier(TOI). The mapping information may be used in a packet, etc. for atransport protocol such as a realtime protocol (RTP), etc.

According to an embodiment of the present invention, mapping informationmay include a header extension type field (HET), a header extensionlength field (HEL), and a uniform resource locator field (URL).

The HET field is the same as in the above description and is notdescribed in detail.

The HEL field indicates an overall length of LCT header extension with avariable length. Basically, when HET has a value between 0 and 127,header extension with a variable length of a 32-bit word unit in LCT,and the HEL field subsequent to the HET field indicates an overalllength of LCT header extension in a 32-bit word unit.

The URL field may be a variable field and may include a session forcurrent transmission, an object, and a unique address on the Internet ofan object internal structure.

Hereinafter, for convenience of description, the URL field may berepresented via mapping information.

The mapping information may indicate URL of signaling information. Inaddition, the mapping information may include an identifier allocated bythe signaling information as well as a session, an object, or a uniqueaddress of an object internal structure. The identifier may include aperiod ID, an adaptation set ID, a representation ID, and a componentID. Accordingly, in the case of MPEG-DASH content, the mappinginformation may include a segment URL, a representation ID, a componentID, an adaptation set ID, a period ID, etc.

For more perfect mapping, signaling information according to anotherembodiment of the present invention may further include mappinginformation for mapping URL of an object or identifier to TOI or TSI.That is, the signaling information may further include a portion of theURL of the object or identifier, to which currently transmitted TOI andTSI are mapped. In this case, the mapping information may be informationfor mapping the URL of the object or identifier to TOI or TSI accordingto one of 1:1, 1:multi, and multi:1.

<Grouping Method of Transport Session and Transport Object>

FIG. 49 is a diagram illustrating a structure of an LCT packet includinggrouping information according to another embodiment of the presentinvention.

According to another embodiment of the present invention, in addition tothe aforementioned method, an object internal structure can beidentified using the grouping information.

An LCT packet according to another embodiment of the present inventionmay include a session group identifier field (SGI) and a dividedtransport session identifier field (DTSI). SGI and DTSI are the formobtained by splitting a legacy transport session identifier field (TSI).

An LCT packet according to another embodiment of the present inventionmay include an object group identifier field (OGI) and a dividedtransport object identifier field (DTOI). OGI and DTOI are the formobtained by splitting a legacy transport object identifier field (TOI).

The S field indicates a length of a legacy TSI field, the O fieldindicates a length of a legacy TOI, and the H field indicates whetherhalf-word (16 bits) is added to a length of a legacy TOI field andlegacy TSI field.

Accordingly, the sum of lengths of the SGI field and DTSI field may bethe same as a legacy TSI field and may be determined based on values ofthe S field and H field. In addition, the sum of lengths of the OGIfield and DTOI field may be the same as a legacy TOI field and may bedetermined based on values of the O field and H field.

According to another embodiment of the present invention, the legacy TSIand TOI may be subdivided into SGI, DTSI, OGI, and DTOI, and SGI, DTSI,OGI, and DTOI may identify different data units.

SGI, DTSI, OGI, and DTO will be described in detail with reference tothe next diagram.

FIG. 50 is a diagram illustrating grouping of a session and an objectaccording to another embodiment of the present invention.

media presentation description (MPD) is an element for providingMPEG-DASH content as a streaming service. For example, theaforementioned presentation may be the concept of one service and maycorrespond to a package of MMT and MPD of MPEG-DASH. MPD C40000 mayinclude at least one period. For example, the MPD C40000 may include afirst period C41000 and a second period C42000.

The Period is an element obtained by dividing MPEG-DASH contentaccording to reproduction time. An available bit rate, a language, acaption, a subtitle, etc. may not be changed in the period. Each periodmay include start time information and periods may be arranged inascending order of a start time in MPD. For example, the first periodC41000 is an element in a period of 0 to 30 min, and the second periodC42000 is an element in a period of 30 to 60 min. A period may includeat least one adaptationset (not shown) as a lower element.

The adaptationset is a set of at least one media content component of aninterchangeable encoded version. The adaptationset may include at leastone Representation as a lower element. For example, The adaptationsetmay include first representation C41100, second representation C41200,and third representation C41300.

Representation may be an element of a transmissible encoded version ofat least one media content component and may include at least one mediastream. A media content component may include a video component, anaudio component, and a caption component. Representation may includeinformation about quality of the media content component. Thus, abroadcast signal receiving apparatus may change representation in oneadaptationset in order to adapt to a network environment.

For example, first representation C41100 may be a video component with afrequency bandwidth of 500 kbit/s, second representation C41200 may be avideo component with a frequency bandwidth of 250 kbit/s, and thirdrepresentation C41300 may be a video component with a frequencybandwidth of 750 kbit/s. Representation may include at least one segmentas a lower element. For example, the first representation C41100 mayinclude a first segment C41110, a second segment C41120, and a thirdsegment C41130.

Segment is an element with a greatest data unit, which can be retrievedaccording to one HTTP request. URL may be provided to each segment. Forexample, the aforementioned object may be the concept corresponding to afile, initialization segment, media segment, or self-initializingsegment, may correspond to a segment of MPEGDASH, and may correspond toMPU of MMT. Each Segment may include at least one fragment as a lowerelement. For example, the second segment C41120 may include a firstfragment C41122, a second fragment C41124, and a third fragment C41126.

Fragment refers to a data unit that can be independently decoded andreproduced without depending upon preceding data. For example, Fragmentmay correspond to subsegment of MPEG-DASH and fragment of MMT. Fragmentmay include at least one chunk or at least one GOP. For example, thefirst fragment C41122 may include a fragment header and a fragmentpayload. The fragment header may include a segment index box (sidx) anda movie fragment box (moof). The fragment payload may include a mediadata container box (mdat). The media data container box (mdat) mayinclude first to fifth Chunks.

The chunk is a set of adjacent samples having the same media type and isa data unit with a variable size.

According to the aforementioned embodiment of the present invention, TSImay identify a transport session, and each representation may be mappedto each TSI. In addition, TOI may identify a transport object in atransport session and each segment may be mapped to each TOI.

However, according to another embodiment of the present invention, TSImay be divided into GSI and DTSI, TOI is divided into OGI and DTOI, andGSI, DTSI, GOI, and DTOI may be mapped to respective new data units,which is not limited to the following embodiment of the presentinvention.

For example, SGI may identify a group of the same transport session andeach period may be mapped to each SGI. A value of SGI of a first periodC41000 may be mapped to “1” and a value of SGI of a second period C42000may be mapped to “2”. The value of SGI may not be limited to theaforementioned embodiment and may have the same value as period ID foridentification of period.

DTSI may identify a transport session and each representation may bemapped to each DTSI. A value of DTSI of the first representation C41100may be mapped to “1”, a value of DTSI of the second representationC41200 may be mapped to “2”, and a value of the DTSI of the thirdrepresentation C41300 may be mapped to “3”. The value of DTSI may not belimited to the aforementioned embodiment and may have the same value asa representation ID for identification of representation.

OGI may identify a group of the same object in a transport session andeach Segment may be mapped to each OGI. A value of OGI of the firstsegment C41110 may be mapped to “1”, a value of OGI of the secondsegment C41120 may be mapped to “2”, and a value of OGI of the thirdsegment C41130 may be mapped to “3”.

DTOI may identify a delivery object. One delivery object may be one ISOBMFF file or a part of one ISO BMFF file. The part of one ISO BMFF filemay include a GOP, a chunk, an access unit and/or an NAL unit.

For example, a fragment header, and each chunk or each GOP of a fragmentpayload may be mapped to each DTOI. A value of DTOI of a header of thefirst fragment C41122 may be mapped to “0” and values of DTOI of firstto fifth chunks in a payload of the first fragment 041122 may be mappedto “10” to “14”.

In the case of DTOI, usage may be defined according to a given value.For example, a DTOI value may be set in an ascending order or adescending order according to an arrangement order of objects. In thiscase, a broadcast signal receiving apparatus may rearrange objects basedon a DTOI value and generate a fragment or a segment. In addition, aspecific DTOI value may indicate a fragment header. In this case, thebroadcast signal transmitting apparatus or the broadcast signalreceiving apparatus may determine whether a fragment header iscompletely transmitted based on the corresponding DTOI value.

If a delivery object means one segment, a group of delivery objects maycorrespond to a content component such as DASH representation. In thiscase, DTIO may be mapped to a segment and OGI may be mapped torepresentation. For example, OGI may be mapped to a representation ID, acontent component ID, etc. in one-to-one correspondence and may be usedas information for multiplexing/demultiplexing content componentstransmitted within one session.

FIG. 51 is a diagram illustrating a structure of a broadcast signaltransmitting apparatus using packet information according to anotherembodiment of the present invention.

The broadcast signal transmitting apparatus may include a signalingencoder C31005, an internal structure generator C31030, a packetinformation generator C31035, and/or a transmitter C31050.

The signaling encoder C31005 may generate signaling informationindicating whether a broadcast signal including multimedia content istransmitted in real time using a broadcast network. The signalinginformation may indicate that multimedia content is transmitted in realtime in at least one of a file level or an FDT level. When the signalinginformation indicates that multimedia content is transmitted in realtime in a file level, all data belonging to the corresponding file canbe transmitted in real time. In addition, when the signaling informationindicates that multimedia content is transmitted in real time in an FDTlevel, all files or data belonging to the corresponding FDT can betransmitted in real time.

The internal structure generator C31030 may generate at least one objectinternal structure as an independently encoded or decoded data unit. Theobject internal structure is obtained by dividing a file included inmultimedia content into at least one data unit.

When the signaling information indicates that multimedia content istransmitted in real time, the packet information generator C31035 maygenerate packet information including metadata for identification of anobject internal structure. Here, the packet information may includemetadata about a packet for transmission of multimedia content andinclude metadata for identification of the object internal structure.The packet information may include boundary information indicating aboundary of the object internal structure and type informationindicating a type of the object internal structure.

The boundary information may include a start flag (SF) field indicatingwhether a corresponding packet includes a start point of an objectinternal structure and an offset field indicating a position of a startpoint of the object internal structure in the corresponding packet.

The type of the object internal structure may include one of a fragmentindicating a data unit including a pair of movie fragment box (moot) andmedia data container box (mdat), Chunk indicating a set of adjacentsamples having the same media type, GOP indicating a set of framesincluding at least one I-frame, an access unit indicating a basic dataunit of encoded video or audio, and a NAL unit indicating a data unitpacketized in a byte unit.

In addition, the packet information may include mapping information formapping at least one of a session, an object, and an object internalstructure to at least one of a transport session identifier (TSI) and atransport object identifier (TOI).

The packet information may include grouping information for grouping atransport session and a transport object transmitted in a packet. Thegrouping information may include a divided transport session identifier(DTSI) field for identification of a transport session, a session groupidentifier (SGI) field for identification of a group having the sametransport session, a divided transport object identifier (DTOI) fieldfor identification of a transport object, and an object group identifier(OGI) field for identification of a group having the same transportobject. Here, the SGI field may include information for identificationof a period element of MPEG-DASH, the DTSI field may include informationfor identification of a representation element of MPEGDASH, the OGIfield may include information for identification of a segment element ofMPEG-DASH, and the DTOI field may include information for identificationof a chunk element of MPEG-DASH.

As described above, the packet information may identity at least one ofa session, an object, and an object internal structure based on typeinformation and boundary information, mapping information, and groupinginformation.

The broadcast signal transmitting apparatus may further include apacketizer (not shown). The packetizer may divide the object internalstructure into at least one symbol with the same size and packetize theat least one symbol as at least one packet. However, the presentinvention is not limited thereto, and the symbol may be generated byanother apparatus. The lengths of symbols according to anotherembodiment of the present invention may be the same. Then the packetizermay packetize at least one symbol as at least one packet. For example,the packet may include a packet header and a packet payload.

The packet header may include packet information for identification ofan object internal structure.

The transmitter C31050 may transmit a broadcast signal including anobject internal structure and packet information.

FIG. 52 is a diagram illustrating a structure of a broadcast signalreceiving apparatus according to another embodiment of the presentinvention.

Hereinafter, common parts of the broadcast signal transmitting apparatusare not described, and the broadcast signal receiving apparatus will bedescribed in terms of differences from the broadcast signal transmittingapparatus.

The broadcast signal receiving apparatus may identify an object internalstructure based on packet information and performing decoding in a unitof received object internal structure. Thus, the broadcast signalreceiving apparatus may not receive one entire object and may produce anobject internal structure despite receiving the object internalstructure.

A broadcast signal receiving apparatus according to another embodimentof the present invention may include a signaling decoder C32005, anextractor C32050, and/or a decoder C32060. However, the broadcast signalreceiving apparatus may further include the aforementioned components.

The signaling decoder C32005 may decode signaling information. Thesignaling information indicates whether a broadcast signal includingmultimedia content is transmitted in real time using a broadcastnetwork.

The extractor C32050 may identify an object internal structure from abroadcast signal and extract the object internal structure. Theextractor C32050 may extract an object internal structure and transmitthe object internal structure to the decoder C32060 based on packetinformation even prior to receiving one entire object. However, anoperation of the extractor C32050 may be changed according to a type ofthe object internal structure. The aforementioned parser C32050 mayperform the same operation as the extractor C32050 and the extractorC32050 may be represented by the parser C32050.

The extractor C32050 may identify a type of a current object internalstructure according to type information and boundary information. Forexample, the extractor C32050 may identify a type of a current objectinternal structure based on a packet corresponding to start and endpoints of the object internal structure represented in the boundaryinformation and type information included in at least one packettransmitted between the start and end points.

The extractor C32050 may extract at least one of an access unit, GOP orchunk, and fragment, which are object internal structures stored in anobject buffer or a segment buffer. To this end, the extractor C32050 mayfurther include an AU extractor C32056 for extracting the access unit, achunk extractor C32057 for extracting chunk or GOP, and a fragmentextractor C32058 for extracting fragment. Lower components of theextractor C32050 will be described in detail with reference to the nextdiagram.

The decoder C32060 may receive the object internal structure and decodethe corresponding object internal structure based on type information.In this case, the decoder C32060 may receive information about theobject internal structure in the form of at least one access unit anddecode at least one access unit to generate Media Data.

FIG. 53 is a diagram illustrating a structure of a broadcast signalreceiving apparatus using packet information according to anotherembodiment of the present invention.

Hereinafter, an operation and configuration of a broadcast signalreceiving apparatus when a type of an object internal structure is anaccess unit will be described.

The broadcast signal receiving apparatus may further include a packetdepacketizer C22020, a segment buffer C32030, an AU extractor C32056, adecoding buffer C32059, and/or a decoder C32060.

The packet depacketizer C22020 may depacketize at least one packet andextract packet information contained in a packet header. For example,the packet depacketizer C22020 may extract type information and boundaryinformation included in the packet header and extract at least onesymbol included in a packet payload. At least one symbol may be a symbolincluded in the object internal structure or a symbol included in anobject.

The packet depacketizer C22020 may transmit the at least one extractedobject or the at least one extracted object internal structure to thedecoder C32060.

The segment buffer C32030 may receive packet of an LCT packet from thepacket depacketizer C22020 and store the data for a predetermined periodof time. The segment buffer C32030 may be repeated by an object bufferC32030. The segment buffer C32030 may further include the AU extractorC32056, a chunk extractor (not shown), and/or a fragment extractor (notshown). In addition, the segment buffer C320300 may further include afragment buffer (not shown) and/or a chunk buffer (not shown).

When type information indicates that the type of the object internalstructure is an access unit, the segment buffer C32030 may include theAU extractor C32056. However, the present invention is not limitedthereto, and the AU extractor C32056 may be present independently fromthe segment buffer C32030.

The AU extractor C32056 may extract the access unit stored in thesegment buffer C32030 based on boundary information. For example, oneaccess unit may be from a start point of the access unit indicated bythe boundary information to a start point of the next access unit.

Then the AU extractor C32056 may transmit the extracted access unit tothe decoder C32060 through the decoding buffer C32059.

As described above, even if the broadcast signal receiving apparatusdoes not receive one entire object, upon completely receiving aninternal structure of the corresponding object based on the typeinformation and boundary information, the AU extractor C32056 mayimmediately extract the object internal structure and may transmit theobject internal structure to the decoder C32060.

The decoding buffer C32059 may receive data from the segment bufferC32030 and store the data for a predetermined period of time. The accessunit may be transmitted to the decoder C32060 or another component for aprocessing time given to the access unit in the decoding buffer C32059.In this case, timing information about the processing time such as apresentation timestamp (PTS), etc. may be given to the access unit inthe form of LCT header extension.

The decoder C32060 may receive the object internal structure and decodethe corresponding object internal structure based on the typeinformation. In this case, the decoder C32060 may receive thecorresponding object internal structure in the form of an access unit aswell as in the form of object internal structure.

When type information indicates that the type of the object internalstructure is an access unit, the decoder C32060 may decode thecorresponding access unit as an internal structure of the correspondingobject even prior to receiving an entire corresponding object.

FIG. 54 is a diagram illustrating a structure of a broadcast signalreceiving apparatus using packet information according to anotherembodiment of the present invention.

The same components as the aforementioned components among thecomponents illustrated in the diagram are the same as in the abovedescription, and thus a detailed description thereof will be omittedherein.

Hereinafter, an operation and configuration of a broadcast signalreceiving apparatus when a type of an object internal structure is chunkor GOP will be described. The broadcast signal receiving apparatus mayfurther include a packet depacketizer C22020, a segment buffer C32030, achunk buffer C32035, a decoding buffer C32059, and/or a decoder C32060.

The packet depacketizer C22020 may transmit at least one extractedobject or at least one object internal structure to the decoder C32060through the segment buffer C32030.

The segment buffer C32030 may include the chunk extractor C32057. Inaddition, the segment buffer C32030 may further include the chunk bufferC32035.

When type information indicates that the type of the object internalstructure is chunk or GOP, the chunk extractor C32057 may extract chunkor GOP stored in the segment buffer C32030 based on boundaryinformation. For example, one chunk or GOP may be from a start point ofthe chunk or GOP indicated by the boundary information to a start pointof the next chunk or GOP. The chunk extractor C32057 may be present inthe segment buffer C32030 or independently.

The chunk buffer C32035 may receive at least one chunk or GOP and storethe chunk or GOP for a predetermined period of time. The chunk bufferC32035 may be present in the segment buffer C32030 or independently. Thechunk buffer C32035 may further include the AU extractor C32056.

The AU extractor C32056 may extract at least one access unit from thechunk or GOP stored in the chunk buffer C32035. Then the AU extractorC32056 may transmit the at least one extracted access unit to thedecoder C32060 through the decoding buffer C32059.

When type information indicates that the type of the object internalstructure is chunk or GOP, the decoder C32060 may decode thecorresponding chunk or GOP as an internal structure of the correspondingobject even prior to receiving an entire corresponding object.

FIG. 55 is a diagram illustrating a structure of a broadcast signalreceiving apparatus using packet information according to anotherembodiment of the present invention.

The same components as the aforementioned components among thecomponents illustrated in the diagram are the same as in the abovedescription, and thus a detailed description thereof will be omittedherein.

Hereinafter, an operation and configuration of a broadcast signalreceiving apparatus when a type of an object internal structure isfragment will be described. The broadcast signal receiving apparatus mayfurther include a packet depacketizer C22020, a segment buffer C32030, afragment buffer C32036, an audio decoding buffer C32059-1, a videodecoding buffer C32059-2, an audio decoder C32060-1, and/or a videodecoder C32060-2.

The packet depacketizer C22020 may transmit at least one extractedobject or at least one extracted object internal structure to the audiodecoder C32060-1 and/or the video decoder C32060-2.

A segment buffer C320300 may include the fragment extractor C32058. Inaddition, the segment buffer C32030 may further include a fragmentbuffer C32036.

When the type information indicates that the type of the object internalstructure is fragment, the fragment extractor C32058 may extractfragment stored in the segment buffer C320300. For example, one fragmentmay be from a start point of the fragment to a start point of the nextfragment. The fragment extractor C32058 may be present in the segmentbuffer C32030 or independently.

The fragment buffer C32036 may receive fragment or store the fragmentfor a predetermined period of time. The fragment buffer C32036 may bepresent in the segment buffer C32030 or independently. The fragmentbuffer C32036 may further include the AU extractor C32056. In thefragment buffer C32036 may further include a chunk buffer (not shown).

The AU extractor C32056 may extract at least one access unit fromfragment stored in the fragment buffer C32036. The AU extractor C32056may be present in the fragment buffer C32036 or independently. Inaddition, the broadcast signal receiving apparatus may further include achunk buffer (not shown), and the AU extractor C32056 may extract atleast one access unit from chunk or GOP included in the chunk buffer.Then the AU extractor C32056 may transmit at least one extracted accessunit to the audio decoder C32060-1 and/or the video decoder C32060-2.

The decoding buffer may include an audio decoding buffer C32059-1 and/ora video decoding buffer C32059-2. The audio decoding buffer C32059-1 mayreceive data associated with audio and store the data for apredetermined period of time. The video decoding buffer C32059-2 mayreceive data associated with video and store the data for apredetermined period of time.

When the type information indicates that the type of the object internalstructure is fragment, the decoder may decode the corresponding fragmentas an internal structure of the corresponding object even prior toreceiving an entire corresponding object. The decoder may furtherinclude the audio decoder C32060-1 for decoding data associated withaudio and/or the video decoder C 32060-2 for decoding data associatedwith video.

As described above, the broadcast signal transmitting apparatus may nottransmit data in an object unit and may transmit data in an objectinternal structure unit with a variable length. In this case, thebroadcast signal transmitting apparatus may transmit the transmittedtype information and boundary information of the object internalstructure.

The broadcast signal receiving apparatus may not reproduce data in anobject unit and may reproduce data in an object internal structure unitwith a variable length. Accordingly, the broadcast signal receivingapparatus may identify an object internal structure based on the typeinformation and boundary information and perform reproduction for eachreceived object internal structure.

<Priority Identification of Transport Packet Payload Data>

FIG. 56 is a diagram showing the structure of a packet includingpriority information according to another embodiment of the presentinvention.

The packet according to another embodiment of the present invention maybe a ROUTE packet and the ROUTE packet may represent an ALC/LCT packet.Hereinafter, for convenience, the ROUTE packet and/or the ALC/LCT packetmay be referred to as an LCT packet. The LCT packet format used by ROUTEfollows the ALC packet format, i.e. the UDP header followed by the LCTheader and the FEC Payload ID followed by the packet payload.

The LCT packet may include a packet header and a packet payload. Thepacket header may include metadata for the packet payload. The packetpayload may include data of MPEG-DASH content.

For example, the packet header may include an LCT version number field(V), a Congestion control flag field (C), a Protocol-Specific Indicationfield (PSI), a Transport Session Identifier flag field (S), a TransportObject Identifier flag field (O), a Half-word flag field (H), a CloseSession flag field (A), a Close Object flag field (B), an LCT headerlength field (HDR_LEN), a Codepoint field (CP), a Congestion ControlInformation field (CCI), a Transport Session Identifier field (TSI), aTransport Object Identifier field (TOI), a Header Extensions field,and/or an FEC Payload ID field.

In addition, the packet payload may include an Encoding Symbol(s) field.

For a detailed description of fields having the same names as theabove-described fields among the fields configuring the LCT packetaccording to another embodiment of the present invention, refer to theabove description.

The packet header may further include priority information (Priority)indicating priority of the packet payload. The priority information mayuse two bits located at twelfth and thirteenth bits from a start pointof each packet to indicate the priority of the packet payload. In thiscase, since two bits are used, it is possible to decrease the size ofthe packet header and to increase efficiency.

The priority information (Priority) may indicate the priority of thepacket payload transmitted using a current LCT packet among the LCTpackets included in one file. That is, the priority information mayindicate relative priority of the packet payload transmitted using acurrent LCT packet among packets having the same TSI or TOI.

For example, the priority information may have a value of 0 to 3. As thevalue of the priority information decreases, the priority of the packetpayload increases in processing of total file-based media data. As thevalue of the priority information increases, the priority of the packetpayload decreases.

TSI may identify an LCT transport session and TOI may identify adelivery object.

Each ROUTE session consists of one or multiple LCT transport sessions.LCT transport sessions are a subset of a ROUTE session. For mediadelivery, an LCT transport session would typically carry a mediacomponent, for example an MPEGDASH Representation. From the perspectiveof broadcast MPEG-DASH, the ROUTE session can be considered as themultiplex of LCT transport sessions that carry constituent mediacomponents of one or more DASH Media Presentations. Within each LCTtransport session, one or multiple Delivery Objects are carried,typically Delivery Objects that are related, e.g. MPEG-DASH Segmentsassociated to one Representation. Along with each Delivery Object,metadata properties are delivered such that the Delivery Objects can beused in applications.

One delivery object may be one ISO BMFF file or a part of one ISO BMFFfile. The part of one ISO BMFF file may include a fragment, a GOP, achunk, an access unit and/or an NAL unit.

As one embodiment, one TSI may match one track (MPEG-DASHrepresentation) and one TOI may match one ISO MBFF file. In addition,one ISO BMFF file may include “ftyp”, “moov”, “moof” and/or “mdat”.

“ftyp” is a container including information about file type andcompatibility. “moov” is a container including all metadata forreproducing media data. If media content is divided into at least onemedia datum within one file or if media content is divided into at leastone file, “moof” is a container including metadata for each dividedmedia data. “mdat” includes media data such as audio data and videodata. “mdat” may include at least one “I-frame”, “P-frame” and/or“B-frame”.

An “I-frame” refers to a frame generated using a spatial compressiontechnique only independent of the frames, instead of a temporalcompression technique using previous and next frames of a correspondingframe in MPEG. Since the “I-frame” is directly coded and generated froman image, the “I-frame” is composed of inter blocks only and may serveas a random access point. In addition, the “I-frame” may be a criterionof a “P-frame” and/or “B-frame” generated by predicting temporal motion.Accordingly, since the “I-frame reduces an extra spatial element of aframe thereof to perform compression, the “I-frame” provides a lowcompression rate. That is, according to the result of compression, thenumber of bits may be greater than the number of bits of other frames.

The “P-frame” means a screen generated by predicting motion with respectto a later scene in MPEG. The “P-frame” is a screen obtained byreferring to a latest “I-frame” and/or “B-frame” and predicting a nextscreen via inter-screen forward prediction only. Accordingly, the“P-frame” provides a relatively high compression rate.

The “B-frame” refers to a predicted screen generated by predictingbidirectional motion in detail from previous and/or next “P-frames”and/or “I-frames” in a temporally predicted screen. The “B-frame” iscoded and/or decoded based on a previous “I-frame” and/or “P-frame”, acurrent frame and/or a next “I-frame” and/or “P-frame”. Accordingly,coding and/or decoding time delay occurs. However, the “B-frame”provides the highest compression rate and does not form the basis ofcoding and/or decoding of the “P-frame” and/or “I-frame” so as not topropagate errors.

As described above, the priorities of “ftyp”, “moov”, “moof” and/or“mdat” in one ISO BMFF file may be different. Accordingly, packetsincluding “ftyp”, “moov”, “moof” and/or “mdat” have the same TSI and/orTOI but may have different priorities.

For example, the priority information of the packet including “ftyp” and“moov” has a value of “0”, the priority information of the packetincluding “moof” has a value of “1”, the priority information of thepacket including the “I-frame” has a value of “1”, the priorityinformation of the packet including the “P-frame” has a value of “2”and/or the priority information of the packet including the “B-frame”has a value of “3”.

The broadcast signal transmission apparatus may assign priorities forpacket data processing in order of a packet including “ftyp” and “moov”,a packet including “moof”, a packet including an “I-Picture”, a packetincluding a “P-Picture” and/or a packet including a “B-Picture”, ifMPEG-DASH segments including video data, such as advanced video coding(AVC)/high efficiency video coding (HEVC), are transmitted.

In addition, intermediate nodes such as a relay and/or a router over anetwork may preferentially transmit a packet having high priority andselectively transmit a packet having low priority, according to networkbandwidth and service purpose. Accordingly, the priority information iseasily applicable to various service states.

In addition, the broadcast signal transmission apparatus maypreferentially extract a packet having high priority (that is, a packethaving a low priority information value) and selectively extract apacket having low priority (that is, a packet having high priorityinformation value), based on the priority information of “ftyp”, “moov”,“moof”, “I-Picture”, “P-Picture” and/or “B-Picture”, when video datasuch as AVC/HEVC is received, thereby configuring one sequence. As amodified embodiment, the broadcast signal reception apparatus mayselectively extract a sequence having a high frame rate and a sequencehaving a low frame rate.

FIG. 57 is a diagram showing the structure of a packet includingpriority information according to another embodiment of the presentinvention.

The packet according to another embodiment of the present invention maybe an LCT packet and the LCT packet may include a packet header and apacket payload. The packet header may include metadata for the packetpayload. The packet payload may include data of MPEG-DASH content.

For example, the packet header may include an LCT version number field(V), a Congestion control flag field (C), a Protocol-Specific Indicationfield (PSI), a Transport Session Identifier flag field (S), a TransportObject Identifier flag field (O), a Half-word flag field (H), a CloseSession flag field (A), a Close Object flag field (B), an LCT headerlength field (HDR_LEN), a Codepoint field (CP), a Congestion ControlInformation field (CCI), a Transport Session Identifier field (TSI), aTransport Object Identifier field (TOI), a Header Extensions field,and/or an FEC Payload ID field.

In addition, the packet payload may include an Encoding Symbol(s) field.

For a detailed description of fields having the same names as theabove-described fields among the fields configuring the LCT packetaccording to another embodiment of the present invention, refer to theabove description.

The packet header may further include priority information (EXT_TYPE)indicating the priority of the packet payload. The priority information(EXT_TYPE) may use an LCT header extension to indicate relative priorityof the packet payload transmitted using a current packet. If the LCTheader extension is used, a broadcast signal reception apparatus whichdoes not support the LCT header extension may skip the priorityinformation (EXT_TYPE), thereby increasing extensibility. The priority:information (EXT_TYPE) using the LCT header extension is applicable to apacket for a transmission protocol such as real-time protocol (RTP).

The priority information (EXT_TYPE) may include a header extension type(HET) field, a priority field and/or a reserved field. According toembodiments, the priority information (EXT_TYPE) may include thepriority field only.

The HET field may be an integer having 8 bits and may indicate the typeof the header extension. For example, the HET field may identify thetype of the header extension using one unique value among values of 128to 255. In this case, the header extension may have a fixed length of 32bits.

The priority field may indicate the priority of the packet payloadtransmitted using a current LCT packet among the LCT packets included inone file. In addition, the priority field may indicate the relativepriority of the packet payload transmitted using the current LCT packetamong the packets having the same TSI or TOI.

For example, the priority information may have a value of 0 to 255. Asthe value of the priority information decreases, the priority of thepacket payload increases in processing of file-based media data.

For example, the priority information of the packet including “ftyp” and“moov” has a value of “0”, the priority information of the packetincluding “moof” has a value of “1”, the priority information of thepacket including the “I-frame” has a value of “2”, the priorityinformation of the packet including the “P-frame” has a value of “3”and/or the priority information of the packet including the “B-fame” hasa value of “4”.

The reserved field may be a field reserved for future use.

Hereinafter, the same description as the above description will beomitted.

FIG. 58 is a diagram showing the structure of a packet including offsetinformation according to another embodiment of the present invention.

The packet according to another embodiment of the present invention maybe an LCT packet and the LCT packet may include a packet header and apacket payload.

The packet header may include metadata for the packet payload. Thepacket payload may include data of MPEG-DASH content.

For example, the packet header may include an LCT version number field(V), a Congestion control flag field (C), a Protocol-Specific Indicationfield (PSI), a Transport Session Identifier flag field (S), a TransportObject Identifier flag field (O), a Half-word flag field (H), a Reservedfield (Res), a Close Session flag field (A), a Close Object flag field(B), an LCT header length field (HDR_LEN), a Codepoint field (CP), aCongestion Control Information field (CCI), a Transport SessionIdentifier field (TSI), a Transport Object Identifier field (TOI), aHeader Extensions field, and/or an FEC Payload ID field.

In addition, the packet payload may include an Encoding Symbol(s) field.

For a detailed description of fields having the same names as theabove-described fields among the fields configuring the LCT packetaccording to another embodiment of the present invention, refer to theabove description.

The packet header may further include offset information. The offsetinformation may indicate an offset within a file of the packet payloadtransmitted using a current packet. The offset information may indicatethe offset in bytes from a start point of the file. The offsetinformation may be in the form of LCT header extension and may beincluded in an FEC payload ID field.

As one embodiment, the case in which the LCT packet includes the offsetinformation (EXT_OFS) in the form of LCT header extension will bedescribed.

If the LCT header extension is used, the receiver which does not supportLCT extension skips the offset information (EXT_OFS), thereby increasingextensibility. The offset information (EXT_OFS) using LCT headerextension is applicable to a packet for a transport protocol such asreal-time protocol (RTP).

The offset information (EXT_OFS) may include a header extension type(HET) field, a header extension length (HEL) field and a start offset(Start Offset) field only.

The HET field is equal to the above description and a detaileddescription thereof will be omitted.

The HEL field indicates the total length of LCT header extension havinga variable length. Fundamentally, in LCT, if the HET has a value of 0 to127, variable-length header extension of a 32-bit word unit exists andthe HEL field following the HET field indicates the total length of LCTheader extension in 32-bit word units.

The start offset field may have a variable length and indicate an offsetwithin a file of the packet payload transmitted using the currentpacket. The start offset field may indicate the offset in bytes from thestart point of the file.

The LCT packet may include the offset information (Start Offset) notonly in the format of LCT header extension but also in an FEC payload IDfield. Hereinafter, the case in which the LCT packet includes the offsetinformation in the FEC payload ID field will be described.

The FEC Payload ID field contains information that indicates to the FECdecoder the relationships between the encoding symbols carried by aparticular packet and the FEC encoding transformation. For example, ifthe packet carries source symbols, then the FEC Payload ID fieldindicates which source symbols of the object are carried by the packet.If the packet carries repair symbols, then the FEC Payload ID fieldindicates how those repair symbols were constructed from the object.

The FEC Payload ID field may also contain information about largergroups of encoding symbols of which those contained in the packet arepart. For example, the FEC Payload ID field may contain informationabout the source block the symbols are related to.

The FEC Payload ID contains Source Block Number (SBN) and/or EncodingSymbol ID (ESI). SBN is a non-negative integer identifier for the sourceblock that the encoding symbols within the packet relate to. ESI is anon-negative integer identifier for the encoding symbols within thepacket.

The FEC payload ID field according to another embodiment of the presentinvention may further include offset information (Start Offset).

An FEC Payload ID field is used that specifies the start address inoctets of the delivery object. This information may be sent in severalways.

First, a simple new FEC scheme with FEC Payload ID set to size 0. Inthis case the packet shall contain the entire object as a direct address(start offset) using 32 bits.

Second, existing FEC schemes that are widely deployed using the CompactNo-Code as defined in RFC 5445 in a compatible manner to RFC 6330 wherethe SBN and ESI defines the start offset together with the symbol sizeT.

Third, the LSID provides the appropriate signaling to signal any of theabove modes using the @sourceFecPayloadID attribute and theFECParameters element.

Hereinafter, the offset information will be described in detail.

In a conventional FLUTE protocol, the offset information did not need tobe transmitted. In the conventional FLUTE protocol, since an object(e.g., a file) is transmitted in non real time, one object was dividedinto at least one data having a fixed size and was transmitted.

For example, in the conventional FLUTE protocol, one object was dividedinto at least one source block having a fixed size, each source blockwas divided into at least one symbol having a fixed size, and a headerwas added to each symbol, thereby generating an LCT packet (or a FLUTEpacket). In the conventional FLUTE protocol, one LCT packet may compriseonly one fixed size symbol.

Since each source block and/or symbol has a fixed size, the receiver mayrecognize the position of each source block and/or symbol within theobject based on identification information of the source block and/orsymbol. Accordingly, the receiver may receive all source blocks and/orsymbols configuring one object and then reconfigure the object based onthe identification information of the received source blocks and/orsymbols.

While the object is transmitted in non real time in the conventionalFLUTE protocol, the object is divided into delivery objects each havinga variable size and is transmitted in real time in delivery object unitsin a ROUTE protocol according to another embodiment of the presentinvention. For example, the ROUTE protocol may transmit the object onthe basis of an object internal structure unit having a variable size.

One delivery object may be one ISO BMFF file or a part of one ISO BMFFfile. The part of one ISO BMFF file may include a fragment, a GOP, achunk, an access unit and/or an NAL unit. The part of one ISO BMFF fieldmay mean the above-described object internal structure. The objectinternal object is an independently meaningful data unit and the type ofthe object internal structure is not limited thereto and may furtherinclude meaningful units.

In the LCT packet according to another embodiment of the presentinvention, each LCT packet (or ALC/LCT packet, ROUTE packet) maycomprise at least one encoding symbol. In the ROUTE protocol accordingto another embodiment of the present invention, one LCT packet maycomprise plural encoding symbols. And, each encoding symbol may bevariable size.

In the LCT packet according to another embodiment of the presentinvention, each TSI may match each track. For example, each TSI maymatch one of a video track, an audio track and/or representation ofMPEG-DASH. In addition, each TOI may be mapped to each delivery object.For example, if TOI is mapped to a segment of MPEG-DASH, the deliveryobject may be an ISO BMFF file. In addition, each TOI may be mapped toone of a fragment, a chunk, a GOP, an access unit and/or an NAL unit.

When the receiver receives LCT packets in real time on the basis of adelivery object unit having a variable size, the receiver may notrecognize where the received LCT packets are located within the object.For example, when the receiver receives LCT packets in an arbitraryorder, the receiver may not align the LCT packets in sequence and maynot accurately restore and/or parse the delivery object.

Accordingly, the offset information according to another embodiment ofthe present invention may indicate the offset of the currentlytransmitted packet payload within the file (e.g., the object). Thereceiver may recognize that the currently transmitted packets have firstdata of the file based on the offset information. In addition, thereceiver may recognize the order of the currently transmitted packetswithin the delivery object based on the offset information. In addition,the receiver may recognize the offset within the file of the packetpayload currently transmitted by the packets and the offset within thefile of the delivery object currently transmitted by the packets, basedon the offset information.

For example, TSI may match video track (MPEG-DASH representation and TOImay match an ISO BMFF file (e.g., an object). In this case; the deliveryobject may represent an ISO BMFF file. One video track (MPEG-DASHrepresentation, TSI=1) may include a first object (TSI=1, TOI=1) and asecond object (TSI=1, TOI=2). The first object (TSI=1, TOI=1) maysequentially include a first packet (TSI=1, TOI=1, Start Offset=0), asecond packet (TSI=1, TOI=1, Start Offset=200), a third packet (TSI=1,TOI=1, Start Offset=400), a fourth packet (TSI=1, TOI=1, StartOffset=800) and a fifth packet (TSI=1, TOI=1, Start Offset=1000).

In this case, if the value of the offset information (Start Offset) is“0”, the packet payload of the packet may have first data of the file.Since the value of the offset information (Start Offset) of the firstpacket is “0”, the receiver may recognize that the packet payload of thefirst packet has first data of the first object.

In addition, the value of the offset information (Start Offset) mayindicate the order of packets within the object. Since the offsetinformation sequentially increases from the first packet to the fifthpacket within the first object, the receiver may recognize that thefirst packet to the fifth packet are sequentially arranged within thefirst object.

Accordingly, the receiver may sequentially align the received LCTpackets within each object and accurately restore each delivery objectand/or object based on the offset information. In addition, the receivermay accurately parse and/or decode each delivery object and/or objectbased on the offset information.

When the receiver receives the LCT packets in real time on the basis ofa delivery object unit having a variable size, the receiver may notrecognize where the received LCT packets are located within the object(e.g., the file). For example, if the LCT packets are transmitted inarbitrary sequence, the receiver may not accurately confirm the offsetwithin the object of the received LCT packets and thus may notaccurately restore the delivery object and/or object via collection ofthe LCT packets.

For example, TSI may match video track (MPEG-DASH representation) andTOI may match a chunk. In this case, one video track (MPEG-DASHrepresentation, TSI=1) may include a first object (TSI=1) and a secondobject (TSI=1). In addition, the first object may include a first chunk(TSI=1, TOI=1), a second chunk (TSI=1, TOI=2) and/or a third chunk(TSI=1, TOI=3) and the second object may include a fourth chunk (TSI=1,TOI=4) and/or a fifth chunk (TSI=1, TOI=5).

The receiver may receive a first packet (TSI=1, TOI=1, Start Offset=0)including a first chunk, a second packet (TSI=1, TOI=2, StartOffset=200) including a second chunk, a third packet (TSI=1, TOI=3,Start Offset=1000) including a third chunk, a fourth packet (TSI=1,TOI=4, Start Offset=0) including a fourth chunk and a fifth packet(TSI=1, TOI=5, Start Offset=1000) including a fifth chunk. Although onepacket includes one chunk in this description, one chunk may include atleast one packet.

If TOI does not match an object (e.g., a file) but matches an objectinternal structure which is a data unit smaller than an object, thereceiver may identify the object unless there is information foridentifying the object.

Accordingly, the receiver may not accurately determine whether thereceived first packet, second packet and/or third packet belong to thefirst object or the second object using TSI and TOI only. In addition,the receiver may not determine whether the received fourth packet and/orfifth packet belong to the first object or the second object using TSIand TOI only.

That is, the receiver may identify that the first packet to the fifthpacket are sequentially arranged based on TSI and TOI but may notidentify whether the third packet belongs to the first object or thesecond object using TSI and TOI only. In addition, the receiver mayidentify that the fifth packet is a next packet of the third packetbased on TSI and TOI but may not identify whether the fourth packetbelongs to the first object or the second object using TSI and TOI only.

In this case, the receiver may not accurately restore the first objecteven when receiving the first packet, the second packet and/or the thirdpacket. In addition, the receiver may not accurately restore the secondobject even when receiving the fourth packet and/or the fifth packet. Asa result, the receiver may not reproduce content in real time.

Accordingly, the LCT packets according to another embodiment of thepresent invention provide offset information (Start Offset). The offsetinformation may indicate the offset of the currently transmitted packetpayload within the object. The receiver may identify the object internalstructure and/or packets included in the same object based on the offsetinformation.

If the value of the offset information is “0”, the packet is a firstpacket of the object. That is, since the offset information of the firstpacket and the fourth packet is “0”, the first packet and the fourthpacket respectively belong to different objects and respectivelyindicate first packets of the respective objects. The receiver mayidentify that the first packet, the second packet and/or the thirdpacket belong to the first object and the fourth packet and the fifthpacket belong to the second object, based on the offset information aswell as TSI and/or TOI.

Accordingly, the receiver identify where the received LCT packets arelocated within each object based on at least one of TSI, TOI and/oroffset information and align the received LCT packets in sequence. Forexample, the receiver may align the packets such that the offsetinformation and TOI sequentially increase.

Then, the receiver may identify a packet having offset information of“0” to a previous packet of a next packet having offset information of“0” using one object. The receiver may identify the delivery objectand/or the object internal structure within one object based on TOI.

In addition, the receiver may accurately restore each delivery objectand/or object.

In addition, the receiver may accurately parse and/or decode eachdelivery object and/or object based on at least one of TSI, TOI and/oroffset information.

As described above, when the transmitter transmits data in objectinternal structure units as an independently meaningful unit, it ispossible to transmit data with a variable size in real time.Accordingly, when the receiver receives and identifies the objectinternal structure even before completely receiving one object, thereceiver may reproduce the object in object internal structure units. Asa result, file (or object) based multimedia content may be transmittedand reproduced via a broadcast network in real time.

FIG. 59 is a diagram showing the structure of a packet including randomaccess point (RAP) information according to another embodiment of thepresent invention.

The packet according to another embodiment of the present invention maybe an LCT packet and the LCT packet may include a packet header and apacket payload. The packet header may include metadata for the packetpayload. The packet payload may include data of MPEG-DASH content.

For example, the packet header may include an LCT version number field(V), a Congestion control flag field (C), a Protocol-Specific Indicationfield (PSI), a Transport Session Identifier flag field (S), a TransportObject Identifier flag field (O), a Half-word flag field (H), a Reservedfield (Res), a Close Session flag field (A), a Close Object flag field(B), an LCT header length field (HDR_LEN), a Codepoint field (CP), aCongestion Control Information field (CCI), a Transport SessionIdentifier field (TSI), a Transport Object Identifier field (TOI), aHeader Extensions field, and an FEC Payload ID field.

In addition, the packet payload may include an encoding symbol(s) field.

For a detailed description of fields having the same names as theabove-described fields among the fields configuring the LCT packetaccording to another embodiment of the present invention, refer to theabove description.

The packet header may further include random access point (RAP)information (P). The RAP information (P) may indicate whether datacorresponding to the random access point (RAP) is included in the packetpayload currently transmitted by the packet. The RAP information (P) mayuse one bit located at a twelfth or thirteenth bit from a start point ofeach packet to indicate whether the data corresponding to the randomaccess point (RAP) is included in the packet payload currentlytransmitted by the packet. In this case, since one bit is used, it ispossible to decrease the size of the packet header and to increaseefficiency.

The random access point (RAP) may be encoded without referring to otherframes and means a basic frame able to be randomly accessed. Forexample, an “I-frame” means a frame which is generated using a spatialcompression technique only independently of other frames without atemporal compression technique using a previous frame and a subsequentframe of a corresponding frame in MPEG. Accordingly, since the “I-frame”is directly coded and generated from an image, the “I-frame” is composedof inter blocks only and may serve as a random access point.

The receiver may identify packets able to be randomly accessed from apacket sequence, which is being transmitted, based on the RAPinformation (P). For example, if the payload of the received packetincludes data about the “I-frame”, the RAP information (P) may indicatethat the packet includes data corresponding to the random access point(RAP). In addition, if the payload of the received packet includes dataabout “B-frame” and/or “P-frame”, the RAP information (P) may indicatethat the packet does not include data corresponding to the random accesspoint (RAP).

When the receiver sequentially receives GOP data starting from aspecific time, if a first packet corresponds to an RAP such as“I-frame”, the receiver may start decoding at that packet. However, ifthe first packet corresponds to a non-RAP such as “B-frame” and/or“P-frame”, the receiver may not start decoding at that packet. In thiscase, the receiver may skip a packet corresponding to a non-RAP andstart decoding at a next packet corresponding to an RAP such as“I-frame”.

Accordingly, in channel tuning in a broadcast environment or inapproaching an arbitrary point within a sequence according to a userrequest, since the receiver skips the packet which does not correspondto the RAP based on the RAP information (P) and starts decoding at thepacket corresponding to the RAP, it is possible to increase packetreception and decoding efficiency.

FIG. 60 is a diagram showing the structure of a packet including randomaccess point (RAP) information according to another embodiment of thepresent invention.

The packet according to another embodiment of the present invention maybe an LCT packet and the LCT packet may include a packet header and apacket payload. The packet header may include metadata for the packetpayload. The packet payload may include data of MPEG-DASH content.

For example, the packet header may include an LCT version number field(V), a Congestion control flag field (C), a Protocol-Specific Indicationfield (PSI), a Transport Session Identifier flag field (S), a TransportObject Identifier flag field (O), a Half-word flag field (H), a Reservedfield (Res), a Close Session flag field (A), a Close Object flag field(B), an LCT header length field (HDR_LEN), a Codepoint field (CP), aCongestion Control Information field (CCI), a Transport SessionIdentifier field (TSI), a Transport Object Identifier field (TOI), aHeader Extensions field, and an FEC Payload ID field.

In addition, the packet payload may include an encoding symbol(s) field.

The packet header may further include random access point (RAP)information (P).

For a detailed description of fields having the same names as theabove-described fields among the fields configuring the LCT packetaccording to another embodiment of the present invention, refer to theabove description.

The RAP information (P) may use one bit located at a sixth or seventhbit from a start point of each packet to, indicate whether datacorresponding to the random access point (RAP) is included in the packetpayload currently transmitted by the packet. In this case, since one bitis used, it is possible to decrease the size of the packet header and toincrease efficiency.

Since the packet according to another embodiment of the presentinvention includes the RAP information (P) using the bit located at thesixth or seventh bit of the packet header, the bit located at thetwelfth or thirteenth bit of the packet header may be used for otherpurposes.

For example, the packet may include the RAP information (P) using thebit located at the sixth or seventh bit of the packet header and includethe above-described object type information and/or priority informationusing the bit located at the twelfth and/or thirteenth bit of the packetheader.

FIG. 61 is a diagram showing the structure of a packet including realtime information according to another embodiment of the presentinvention.

The packet according to another embodiment of the present invention maybe an LCT packet and the LCT packet may include a packet header and apacket payload. The packet header may include metadata for the packetpayload. The packet payload may include data of MPEG-DASH content.

For example, the packet header may include an LCT version number field(V), a Congestion control flag field (C), a Protocol-Specific Indicationfield (PSI), a Transport Session Identifier flag field (S), a TransportObject Identifier flag field (O), a Half-word flag field (H), a Reservedfield (Res), a Close Session flag field (A), a Close Object flag field(B), an LCT header length field (HDR_LEN), a Codepoint field (CP), aCongestion Control Information field (CCI), a Transport SessionIdentifier field (TSI), a Transport Object Identifier field (TOI), aHeader Extensions field, and/or an FEC Payload ID field.

In addition, the packet payload may include an encoding symbol(s) field.

For a detailed description of fields having the same names as theabove-described fields among the fields configuring the LCT packetaccording to another embodiment of the present invention, refer to theabove description.

The transmitter may indicate whether the object and/or object internalstructure transmitted by the LCT packet is transmitted in real time orin non real time via real time information (T) defined at a filedelivery table (FDT) level and/or a delivery object level. The deliveryobject level may include an object level and/or an object internalstructure level.

If the real time information (T) is defined at the FDT level, the realtime information (T) may indicate whether all data described in the FDTis transmitted in real time or non real time. For example, an LSID mayinclude real time information (T). In addition, if the real timeinformation (T) is defined at the FDT level, the real time information(T) may indicate whether all objects described in the FDT aretransmitted in real time or in non real time. Here, all objectsdescribed in the FDT may indicate all objects belonging to acorresponding LCT transport session.

In addition, if the real time information (T) is defined at the deliveryobject level, the real time information (T) may indicate whether alldata belonging to the delivery object is transmitted in real time or innon real time. For example, if the delivery object matches an object andthe real time information (T) is defined at the delivery object level,the real time information T may indicate whether all data belonging tothe object is transmitted in real time or in non real time. In addition,if the delivery object matches an object internal structure and the realtime information (T) is defined at the delivery object level, the realtime information (T) may indicate whether all data belonging to theobject internal structure is transmitted in real time or in non realtime.

As one embodiment, if the real time information (T) is defined at thedelivery object level, the packet header may further include real timeinformation (T). The real time information (T) may indicate whether thedelivery object transmitted by the LCT packet is transmitted in realtime or in non real time.

For example, the delivery object may be a data unit matching TOI. Inaddition, the value of the real time information (T) of “0” may indicatethat the delivery object transmitted by the LCT packet is transmitted innon real time and the value of the real time information (T) of “1” mayindicate that the delivery object transmitted by the LCT packet istransmitted in real time.

The real time information (T) may use a first bit of a TOI field toindicate that the delivery object transmitted by the LCT packet istransmitted in real time or in non real time.

As described above, if the TOI field is divided into an OGI field and aDTOI field, the real time information (T) may use a first bit of the OGIfield to indicate whether the delivery object transmitted by the LCTpacket is transmitted in real time or in non real time.

Since the real time information (T) is included in the first bit of theTOI field and/or the OGI field, the transmitter may transmit real-timedata and non-real-time data within one LCT transport session (e.g.,video track, audio track and representation of MPEG-DASH). For example,the transmitter may transmit audio data and/or video data within one LCTtransport session in real time and transmit an image and/or anapplication in non real time. In addition, the transmitter may transmitsome delivery objects within one LCT transport session in real time andtransmit the remaining delivery objects in non real time.

In addition, since the real time information (T) is included in a firstbit of an existing TOI field, the LCT packet according to anotherembodiment of the present invention can guarantee backward compatibilitywith an existing ALC/LCT and/or FLUTE protocol.

FIG. 62 is a diagram showing the structure of a broadcast signaltransmission apparatus according to another embodiment of the presentinvention.

The broadcast signal transmission apparatus according to anotherembodiment of the present invention may include a delivery objectgenerator C51300, a signaling encoder C51100 and/or a transmitterC31500.

The delivery object generator may divide a file into at least onedelivery object corresponding to a part of the file.

The signaling encoder may encode signaling information includingmetadata for the delivery object.

The signaling information may include real time information indicatingwhether at least one delivery object is transmitted in real time via aunidirectional channel using at least one layered coding transport (LCT)packet.

The transmitter may transmit at least one delivery object and signalingin formation.

The broadcast signal transmission apparatus according to anotherembodiment of the present invention may include all the functions of theabove-described broadcast signal transmission apparatus. In addition,for a detailed description of the signaling information, refer to theabove description or the following description of a subsequent figure.

FIG. 63 is a diagram showing the structure of a broadcast signalreception apparatus according to another embodiment of the presentinvention.

The broadcast signal reception apparatus may receive a broadcast signal.The broadcast signal may include signaling data, ESG data, NRT contentdata and/or RT content data.

The broadcast signal reception apparatus may join in a ROUTE sessionbased on a ROUTE session description. The ROUTE session description mayinclude an IP address of the broadcast signal transmission apparatus andan address and port number of a ROUTE session, the session is an ROUTEsession, and all packets may include information indicating an LCTpacket. In addition, the ROUTE session description may further includeinformation necessary to join in and consume the session using anIP/UDP.

Then, the broadcast signal reception apparatus may receive an LCTsession instance description (LSID) including information about at leastone LCT transport session included in the ROUTE session.

Then, the broadcast signal reception apparatus may receive multimediacontent included in at least one LCT transport session. The multimediacontent may be composed of at least one file. The broadcast signalreception apparatus may receive file based multimedia content in realtime via a unidirectional channel using a layered coding transport (LCT)packet.

The broadcast signal reception apparatus according to another embodimentof the present invention may include a signaling decoder C52100, adelivery object processor C52300 and/or a decoder C52500.

The signaling decoder C52100 may decode signaling information includingmetadata for at least one delivery object corresponding to a part of afile.

The signaling information may include real time information indicatingwhether at least one delivery object is transmitted in real time via aunidirectional channel using a layered coding transport (LCT) packet.The signaling information may be included not only in an LSID but alsoin an extended header of the LCT packet.

The real time information is defined in a file delivery table (FDT) andmay indicate whether all delivery objects described in the FDT aretransmitted in real time. In addition, the real time information isdefined by a first bit of a transport object identifier (TOI) field foridentifying the delivery object and may indicate whether all databelonging to the delivery object is transmitted in real time.

The delivery object processor C52300 may collect at least one LCT packetand restore at least one delivery object. The delivery object processorC52300 may include functions of the above-described transmission blockregenerator C22030, fragment regenerator C22040 and fragment parserC22050 and/or extractor C32050.

The decoder C52500 may decode at least one delivery object. The decoderC52500 may receive information about the delivery object in the form ofat least one access unit, decode the at least one access unit andgenerate media data. The decoder C52500 may decode the delivery object,upon receiving the delivery object corresponding to the part of thefile, although one file is not completely received.

The signaling information may further include offset informationindicating the offset of data transmitted by the LCT packet within thefile. The delivery object processor C52300 may identify the deliveryobject based on the offset information. The offset information may beindicated in bytes from the start point of the file. The offsetinformation may be in the form of an LCT header extension and may beincluded in an FEC payload ID field.

When the broadcast signal reception apparatus receives the LCT packet inreal time on the basis of a delivery object unit having a variable size,the receiver may not recognize where the received LCT packets arelocated in the object. For example, when the receiver receives LCTpackets in an arbitrary order, the receiver may not align the LCTpackets in sequence and may not accurately restore and/or parse thedelivery object.

Accordingly, the offset information according to another embodiment ofthe present invention may indicate the offset of the currentlytransmitted packet payload within the file (e.g., the object). Thebroadcast signal reception apparatus may recognize that the currentlytransmitted packets have first data of the file based on the offsetinformation. In addition, the broadcast signal reception apparatus mayrecognize the order of the currently transmitted LCT packets within thefile and/or the delivery object based on the offset information.

The broadcast signal reception apparatus may recognize the offset withinthe file of the packet payload currently transmitted by the LCT packetsand the offset within the file of the delivery object currentlytransmitted by the LCT packets, based on the offset information.

If TOI does not match an object (e.g., a file) but matches an objectinternal structure which is a data unit smaller than an object; thebroadcast signal reception apparatus may identify the object unlessthere is no information for identifying the object.

Accordingly, the broadcast signal reception apparatus may identify theobject internal structure and/or the LCT packets included in the sameobject based on the offset information.

The signaling information may further include RAP information indicatingwhether the LCT packet includes data corresponding to a random accesspoint (RAP). The random access point may be encoded without referring toother frames and means a basic frame able to be randomly accessed.

The delivery object processor C52300 may collect at least one packetfrom packets for transmitting data corresponding to the random accesspoint based on the RAP information.

For example, when the broadcast signal reception apparatus sequentiallyreceives GOP data starting from a specific time, if a first packetcorresponds to an RAP such as “I-frame”, the broadcast signaltransmission apparatus may start decoding at that LCT packet. However,if the first packet corresponds to a non-RAP such as “B-frame” and/or“P-frame”, the broadcast signal reception apparatus may not startdecoding at that packet. In this case, the receiver may skip an LCTpacket corresponding to a non-RAP and start decoding at an LCT packetcorresponding to an RAP such as “I-frame”.

The signaling information may further include priority informationindicating the priority of the data transmitted by the LCT packets.

The delivery object process C52300 may selectively collect the LCTpackets based on the priority information.

The broadcast signal reception apparatus may preferentially extract LCTpackets having high priority and selectively extract LCT packets havinglow priority, based on the priority information of ‘ftyp’, ‘moov’,‘moof’, ‘I-Picture’, ‘P-Picture’, and/or ‘B-Picture’, when receivingvideo data such as AVC/HEVC, thereby configuring one sequence.

FIG. 64 is a view showing a protocol stack for a next generationbroadcasting system according to an embodiment of the present invention.

The broadcasting system according to the present invention maycorrespond to a hybrid broadcasting system in which an Internet Protocol(IP) centric broadcast network and a broadband are coupled.

The broadcasting system according to the present invention may bedesigned to maintain compatibility with a conventional MPEG-2 basedbroadcasting system.

The broadcasting system according to the present invention maycorrespond to a hybrid broadcasting system based on coupling of an IPcentric broadcast network, a broadband network, and/or a mobilecommunication network (or a cellular network).

Referring to the figure, a physical layer may use a physical protocoladopted in a broadcasting system, such as an ATSC system and/or a DVBsystem. For example, in the physical layer according to the presentinvention, a transmitter/receiver may transmit/receive a terrestrialbroadcast signal and convert a transport frame including broadcast datainto an appropriate form.

In an encapsulation layer, an IP datagram is acquired from informationacquired from the physical layer or the acquired IP datagram isconverted into a specific frame (for example, an RS Frame, GSE-lite,GSE, or a signal frame). The frame main include a set of IP datagrams.For example, in the encapsulation layer, the transmitter include dataprocessed from the physical layer in a transport frame or the receiverextracts an MPEG-2 TS and an IP datagram from the transport frameacquired from the physical layer.

A fast information channel (FIC) includes information (for example,mapping information between a service ID and a frame) necessary toaccess a service and/or content. The FIC may be named a fast accesschannel (FAC).

The broadcasting system according to the present invention may useprotocols, such as an Internet Protocol (IP), a User Datagram Protocol(UDP), a Transmission Control Protocol (TCP), an Asynchronous LayeredCoding/Layered Coding Transport (ALC/LCT), a Rate Control Protocol/RTPControl Protocol (RCP/RTCP), a Hypertext Transfer Protocol (HTTP), and aFile Delivery over Unidirectional Transport (FLUTE). A stack betweenthese protocols may refer to the structure shown in the figure.

In the broadcasting system according to the present invention, data maybe transported in the form of an ISO based media file format (ISOBMFF).An Electrical Service Guide (ESG), Non Real Time (NRT), Audio/Video(A/V), and/or general data may be transported in the form of theISOBMFF.

Transport of data through a broadcast network may include transport of alinear content and/or transport of a non-linear content.

Transport of RTP/RTCP based AN and data (closed caption, emergency alertmessage, etc.) may correspond to transport of a linear content.

An RTP payload may be transported in the form of an RTP/AV streamincluding a Network Abstraction Layer (NAL) and/or in a formencapsulated in an ISO based media file format. Transport of the RTPpayload may correspond to transport of a linear content. Transport inthe form encapsulated in the ISO based media file format may include anMPEG DASH media segment for AN, etc.

Transport of a FLUTE based ESG, transport of non-timed data, transportof an NRT content may correspond to transport of a non-linear content.These may be transported in an MIME type file form and/or a formencapsulated in an ISO based media file format. Transport in the formencapsulated in the ISO based media file format may include an MPEG DASHmedia segment for A/V, etc.

Transport through a broadband network may be divided into transport of acontent and transport of signaling data.

Transport of the content includes transport of a linear content (A/V anddata (closed caption, emergency alert message, etc.)), transport of anon-linear content (ESG, nontimed data, etc.), and transport of a MPEGDASH based Media segment (A/V and data).

Transport of the signaling data may be transport including a signalingtable (including an MPD of MPEG DASH) transported through a broadcastingnetwork.

In the broadcasting system according to the present invention,synchronization between linear/non-linear contents transported throughthe broadcasting network or synchronization between a contenttransported through the broadcasting network and a content transportedthrough the broadband may be supported. For example, in a case in whichone UD content is separately and simultaneously transported through thebroadcasting network and the broadband, the receiver may adjust thetimeline dependent upon a transport protocol and synchronize the contentthrough the broadcasting network and the content through the broadbandto reconfigure the contents as one UD content.

An applications layer of the broadcasting system according to thepresent invention may realize technical characteristics, such asInteractivity, Personalization, Second Screen, and automatic contentrecognition (ACR). These characteristics are important in extension fromATSC 2.0 to ATSC 3.0. For example, HTML5 may be used for acharacteristic of interactivity.

In a presentation layer of the broadcasting system according to thepresent invention, HTML and/or HTML5 may be used to identify spatial andtemporal relationships between components or interactive applications.

In the present invention, signaling includes signaling informationnecessary to support effective acquisition of a content and/or aservice. Signaling data may be expressed in a binary or XMK form. Thesignaling data may be transmitted through the terrestrial broadcastingnetwork or the broadband:

A real-time broadcast A/V content and/or data may be expressed in an ISOBase Media File Format, etc. In this case, the A/V content and/or datamay be transmitted through the terrestrial broadcasting network in realtime and may be transmitted based on IP/UDP/FLUTE in non-real time.Alternatively, the broadcast A/V content and/or data may be received byreceiving or requesting a content in a streaming mode using DynamicAdaptive Streaming over HTTP (DASH) through the Internet in real time.In the broadcasting system according to the embodiment of the presentinvention, the received broadcast A/V content and/or data may becombined to provide various enhanced services, such as an Interactiveservice and a second screen service, to a viewer.

An example of the physical layer (a Broadcast PHY and a Broadband PHY)of the transmitter may be the structure shown in FIG. 1. An example ofthe physical layer of the receiver may be the structure shown in FIG. 9.

The signaling data and the IP/UDP datagram may be transmitted through aspecific data pipe (hereinafter, DP) of a transport frame (or a frame)delivered to the physical layer. For example, the input formatting block1000 may receive signaling data and IP/UDP datagram and demultiplex eachof the signaling data and the IP/UDP datagram into at least one DP. Theoutput processor 9300 may perform an operation contrary to that of theinput formatting block 1000.

FIG. 65 illustrates a receiver of a next generation broadcasting systemaccording to an embodiment of the present invention.

The receiver according to the present embodiment may include a receivingunit (not illustrated), a channel synchronizer J32010, a channelequalizer J32020, a channel decoder J32030, a signaling decoder J32040,a baseband operation controller J32050, a service map database (DB)J32060, a transport packet interface J32070, a broadband packetinterface J32080, a common protocol stack J32090, a service signalingchannel processing buffer & parser J32100, an A/V processor J32110, aservice guide processor J32120, an application processor J32130 and/or aservice guide DB J32140.

The receiving unit (not illustrated) receives a broadcast signal.

The channel synchronizer J32010 synchronizes a symbol frequency andtiming so as to decode a signal received in a baseband. Here, thebaseband refers to a region in which the broadcast signal istransmitted/received.

The channel equalizer J32020 performs channel equalization upon areceived signal. The channel equalizer J32020 compensates for thereceived signal when the signal is distorted due to multipath, Dopplereffect, or the like.

The channel decoder J32030 restores the received signal to a meaningfultransport frame. The channel decoder J32030 performs forward errorcorrection (FEC) on data or a transport frame included in the receivedsignal.

The signaling decoder J32040 extracts and decodes signaling dataincluded in the received signal. Here, the signaling data includessignaling data and/or service information to be described below.

The baseband operation controller J32050 controls processing of a signalin the baseband.

The service map DB J32060 stores the signaling data and/or the serviceinformation. The service map DB J32060 may store signaling data which istransmitted by being included in a broadcast signal and/or the signalingdata which is transmitted by being included in a broadband packet.

The transport packet interface J32070 extracts a transport packet from atransport frame or a broadcast signal. The transport packet interfaceJ32070 extracts signaling data or an IP datagram from the transportpacket.

The broadband packet interface J32080 receives a broadcasting-relatedpacket through the Internet. The broadband packet interface J32080extracts the packet acquired through the Internet, and combines orextracts signaling data or AN data from the packet.

The common protocol stack J32090 processes a received packet accordingto a protocol which is included in a protocol stack. For example, thecommon protocol stack J32090 may process the received packet accordingto the above-described protocol stack.

The service signaling channel processing buffer & parser J32100 extractssignaling data included in the received packet. The service signalingchannel processing buffer& parser J32100 extracts signaling informationrelated to scanning and/or acquisition of a service and/or content froman IP datagram and the like, and parses the extracted signalinginformation. The signaling data may be present at a certain position orchannel in the received packet. The position or channel may be referredtows a service signaling channel. For example, the service signalingchannel may have a particular IP address, a UDP port number, atransmission session identifier, and the like. The receiver mayrecognize data transmitted to the particular IP address, the UDP portnumber, the transmission session, and the like as signaling data.

The A/V processor J32110 decodes and presents received AN data.

The service guide processor J32120 extracts announcement informationfrom the received signal, manages the service guide DB J32140 andprovides a service guide.

The application processor J32130 extracts application data and/orapplication-related information included in the received packet, andprocesses the extracted data and/or information.

The service guide DB J32140 stores service guide data.

FIG. 66 is a view showing a broadcast receiver according to anembodiment of the present invention.

The broadcast receiver according to an embodiment of the presentinvention includes a service/content acquisition controller J2010, anInternet interface J2020, a broadcast interface J2030, a signalingdecoder J2040, a service map database J2050, a decoder J2060, atargeting processor J2070, a processor J2080, a managing unit J2090,and/or a redistribution module J2100. In the figure is shown an externalmanagement device J2110 which may be located outside and/or in thebroadcast receiver.

The service/content acquisition controller J2010 receives a serviceand/or content and signaling data related thereto through abroadcast/broadband channel. Alternatively, the service/contentacquisition controller J2010 may perform control for receiving a serviceand/or content and signaling data related thereto.

The Internet interface J2020 may include an Internet access controlmodule. The Internet access control module receives a service, content,and/or signaling data through a broadband channel. Alternatively, theInternet access control module may control the operation of the receiverfor acquiring a service, content, and/or signaling data.

The broadcast interface J2030 may include a physical layer module and/ora physical layer I/F module. The physical layer module receives abroadcast-related signal through a broadcast channel. The physical layermodule processes (demodulates, decodes, etc.) the broadcast-relatedsignal received through the broadcast channel. The physical layer I/Fmodule acquires an Internet protocol (IP) datagram from informationacquired from the physical layer module or performs conversion to aspecific frame (for example, a broadcast frame, RS frame, or GSE) usingthe acquired. IP datagram.

The signaling decoder J2040 decodes signaling data or signalinginformation (hereinafter, referred to as ‘signaling data’) acquiredthrough the broadcast channel, etc.

The service map database J2050 stores the decoded signaling data orsignaling data processed by another device (for example, a signalingparser) of the receiver.

The decoder J2060 decodes a broadcast signal or data received by thereceiver. The decoder J2060 may include a scheduled streaming decoder, afile decoder, a file database (DB), an on-demand streaming decoder, acomponent synchronizer, an alert signaling parser, a targeting signalingparser, a service signaling parser, and/or an application signalingparser.

The scheduled streaming decoder extracts audio/video data for real-timeaudio/video (A/V) from the IP datagram, etc. and decodes the extractedaudio/video data.

The file decoder extracts file type data, such as NRT data and anapplication, from the IP datagram and decodes the extracted file typedata.

The file DB stores the data extracted by the file decoder.

The on-demand streaming decoder extracts audio/video data for on-demandstreaming from the IP datagram, etc. and decodes the extractedaudio/video data.

The component synchronizer performs synchronization between elementsconstituting a content or between elements constituting a service basedon the data decoded by the scheduled streaming decoder, the filedecoder, and/or the on-demand streaming decoder to configure the contentor the service.

The alert signaling parser extracts signaling information related toalerting from the IP datagram, etc. and parses the extracted signalinginformation.

The targeting signaling parser extracts signaling information related toservice/content personalization or targeting from the IP datagram, etc.and parses the extracted signaling information. Targeting is an actionfor providing a content or service satisfying conditions of a specificviewer. In other words, targeting is an action for identifying a contentor service satisfying conditions of a specific viewer and providing theidentified content or service to the viewer.

The service signaling parser extracts signaling information related toservice scan and/or a service/content from the IP datagram, etc. andparses the extracted signaling information. The signaling informationrelated to the service/content includes broadcasting system informationand/or broadcast signaling information.

The application signaling parser extracts signaling information relatedto acquisition of an application from the IP datagram, etc. and parsesthe extracted signaling information. The signaling information relatedto acquisition of the application may include a trigger, a TDO parametertable (TPT), and/or a TDO parameter element.

The targeting processor J2070 processes the information related toservice/content targeting parsed by the targeting signaling parser.

The processor J2080 performs a series of processes for displaying thereceived data.

The processor J2080 may include an alert processor, an applicationprocessor, and/or an A/V processor.

The alert processor controls the receiver to acquire alert data throughsignaling information related to alerting and performs a process fordisplaying the alert data.

The application processor processes information related to anapplication and processes a state of an downloaded application and adisplay parameter related to the application.

The AN processor performs an operation related to audio/video renderingbased on decoded audio data, video data, and/or application data.

The managing unit J2090 includes a device manager and/or a data sharing& communication unit.

The device manager performs management for an external device, such asaddition/deletion/renewal of an external device that can be interlocked,including connection and data exchange.

The data sharing & communication unit processes information related todata transport and exchange between the receiver and an external device(for example, a companion device) and performs an operation relatedthereto. The transportable and exchangeable data may be signaling data,a PDI table, PDI user data, PDI Q&A, and/or A/V data.

The redistribution module J2100 performs acquisition of informationrelated to a service/content and/or service/content data in a case inwhich the receiver cannot directly receive a broadcast signal.

The external management device J2110 refers to modules, such as abroadcast service/content server, located outside the broadcast receiverfor providing a broadcast service/content. A module functioning as theexternal management device may be provided in the broadcast receiver.

FIG. 67 illustrates a timeline component for synchronization between atransport stream in the broadcasting network and a transport stream inthe Internet (heterogeneous network) according to an embodiment of thepresent invention.

There is a possibility that streams transmitted through heterogeneousnetworks such as the broadcasting network and the Internet may besynchronized and used for one service in the receiver of theabove-described broadcasting system. For example, as illustrated, when avideo stream is transmitted through the broadcasting network and anaudio stream is transmitted through the Internet, the two streams needto be synchronized, decoded and reproduced for one service. In otherwords, video is acquired over the broadcasting network and audio isacquired over the Internet to use one service. For example, a viewer whodesires to view the same content using audio recorded in a differentlanguage from a language provided in the broadcasting network mayreceive the audio of the corresponding content recorded in the desiredlanguage through the Internet and use the received audio.

However, the two streams have different timelines and thus a mechanismis needed to perform mapping between the two timelines. Here, each ofthe timelines may indicate absolute or relative time serving as acriterion for reproduction or decoding of data or content transmittedthrough each transport network. In a service, content contained in videotransmitted through the broadcasting network needs to be identical tocontent contained in audio transmitted through the Internet.

The present embodiment proposes a method and apparatus for using atimeline component for synchronization between streams transmittedthrough heterogeneous networks such as the broadcasting network and theInternet. A timeline component stream may include one or more timelinecomponent access units (AUs). The timeline components AU may becontiguously disposed in the timeline component.

The timeline component AU shows an example in which a timeline of astream transmitted through the Internet is mapped to a timeline of astream transmitted through the broadcasting network. When a header of apacket transmitted through the broadcasting network includes informationabout the timeline of the stream transmitted through the broadcastingnetwork, a timeline component AU transmissible through the broadcastingnetwork may include timestamp information and the like such as adecoding timestamp (DTS), a presentation timestamp (PTS), and the likeof a stream transmitted through a heterogeneous network (for example,the Internet). When information about a timeline of the streamtransmitted through the heterogeneous network (for example, theInternet) is included in the timeline component AU, the informationabout the timeline of the stream transmitted through the heterogeneousnetwork (for example, the Internet) may be packetized in the same packetstructure as that of the stream transmitted through the broadcastingnetwork. In this way, a timestamp of the stream transmitted through thebroadcasting network included in the packet header may be mapped to atimestamp of the stream transmitted through the Internet on a one-to-onebasis, and both the streams may be synchronized in one timeline, anddecoded and reproduced. The aforementioned timestamp information mayrepresent a timeline reference value for constituting a timeline of astream transmitted over an external network (e.g., a heterogeneousnetwork, an Internet network, etc.).

The presentation timestamp (PTS) is a timestamp metadata field in anMPEG transport stream, MPEG program stream or similar data stream thatis used to achieve synchronization of programs' separate elementarystreams (for example Video, Audio, Subtitles) when presented to theviewer. The PTS is given in units related to a program's overall clockreference, either Program Clock Reference (PCR) or System ClockReference (SCR), which is also transmitted in the transport stream orprogram stream.

The Decode Timestamp (DTS) indicates the time at which an access unitshould be instantaneously removed from the receiver buffer and decoded.It differs from the Presentation Timestamp (PTS) only when picturereordering is used for B pictures. If DTS is used, PTS may be providedin the bit stream.

The above description may be applied to a case in which streamstransmitted through one network use different timelines. For example,when the above-described scheme is used, a relay service provider, whocollects streams transmitted through a plurality of heterogeneousnetworks and provides the streams to viewers, does not need to directlyperform reprocessing for synchronization of different streams.

FIG. 68 illustrates syntax of the timeline component AU according to anembodiment of the present invention.

The timeline component AU may be expressed in another format such as XMLor the like.

The timeline component AU may include identifier information, versioninformation, AU_length information, location_flag information, PTS_flaginformation, DTS_flag information, media_time_flag information,NTP_time_flag information, PTP_time_flag information, timecode_flaginformation, PCR_time_flag information, location_length information,location information, timescale information, media_time_PTS information,media_time_DTS information, NTP_time_PTS information, NTP_time_DTSinformation, PTP_time_PTS information, PTP_time_DTS information,timecode_PTS information, timecode_DTS information, PCR_time_PTSinformation, and/or PCR_time_DTS information.

The identifier information is an identifier that uniquely indicates astructure of the timeline component AU.

The version information may indicate lengths of timestamp fields such asa lower PTS, DTS and the like. For example, the length may correspond to64 bits when the version information has a value of 1, and correspond to32 bits when the version information has a value of 0.

The AU_length information indicates a length of the timeline componentAU.

The location_flag information indicates whether the timeline componentAU includes location information of a stream transmitted through anexternal network.

The PTS_flag information indicates whether the timeline component AUincludes a PTS value.

The DTS_flag information indicates whether the timeline component AUincludes a DTS value.

The media_time_flag information indicates whether a timestamp having amedia time format is included.

The NTP_time_flag information indicates whether a timestamp having anNTP format is included.

The PTP_time_flag information indicates whether a timestamp having a PTPformat is included.

The timecode_flag information indicates whether a timestamp having asociety of motion picture and television engineers (SMPTE) time codeformat is included.

The PCR_time_flag information indicates whether a PCR-based timestamp ofan MPEG-2 TS is included.

The location_length information indicates a length of a location field.

The location information indicates a URL or a unique ID of a streamtransmitted through a heterogeneous network. When the locationinformation indicates the unique ID, the location information may beused by being linked to information such as signaling data or the like.

The timescale information indicates a media timescale. The timescaleinformation is information for identifying a unit of time indicated byother information.

The media_time_PTS information indicates a PTS expressed in a media timeformat.

The media_time_DTS information indicates a DTS expressed in a media timeformat.

The NTP_time_PTS information indicates a PTS expressed in an NPT format.

The NTP_time_DTS information indicates a DTS expressed in an NPT format.

The PTP_time_PTS information indicates a PTS expressed in a PTP format.

The PTP_time_DTS information indicates a DTS expressed in a PTP format.

The timecode_PTS information indicates a PTS expressed in an SMPTE timecode format.

The timecode_DTS information indicates a DTS expressed in an SMPTE timecode format.

The PCR_time_PTS information indicates a PTS expressed in a PCR format.

The PCR_time_DTS information indicates a DTS expressed in a PCR format.

According to an embodiment of the present invention, the receiver maysynchronize a stream transmitted through the broadcasting network with astream transmitted through a heterogeneous network by applying at leastone timestamp information included in the timeline component AU to astream in an external network which is identified by the locationinformation.

FIG. 69 illustrates syntax of the timeline component AU according toanother embodiment of the present invention.

The timeline component AU may be expressed in another format such as XMLor the like.

The timeline component AU may include identifier information, versioninformation, AU_length information, location_flag information, PTS_flaginformation, DTS_flag information, timestamp_version_flag information,timestamp_type information, location_length information, locationinformation, timescale information, media_time_PTS information,media_time_DTS information, timestamp_type_PTS information, and/ortimestamp_to DTS information (or timestamp_type_DTS information).

Description of information corresponding to the same term as that of theinformation included in syntax of the timeline component AU describedabove is replaced by the above description.

The timestamp_version_flag information indicates a timestamp format of atimeline to be mapped. For example, it is possible to indicate that a32-bit format is to be used when the timestamp_version_flag informationhas a value of 0, and a 64-bit format is to be used when thetimestamp_version_flag information has a value of 1.

The timestamp_type information indicates a type of a timestamp of atimeline to be mapped. For example, the timestamp_type informationindicates that the type corresponds to a media time when the informationhas a value of 0x00, indicates that the type corresponds to NTP when theinformation has a value of 0x01, indicates that the type corresponds toPTP when the information has a value of 0x02, and indicates that thetype corresponds to a time code when the information has a value of0x03. When the information has a value of 0x04-0x1F, the type may bedefined later, and the value may be reserved.

The timescale information may indicate a timescale that expresses amedia time of a timeline to be mapped. For example, in an MPEG-2 TS, thetimescale may have a value of 90K.

The media_time_PTS information may indicate a presentation timestamp ofa timeline to be mapped, that is, a media time with respect to a pointin time at which reproduction is performed. The media_time_PTSinformation may be indicated by a 32-bit format when atimestamp_version_flag value is 0, and indicated by a 64-bit format whenthe value is 1.

The media_time_DTS information may indicate a decoding timestamp of atimeline to be mapped, that is, a media time with respect to a point intime at which decoding is performed. The media_time_DTS information maybe indicated by a 32-bit format when a timestamp_version_flag value is0, and indicated by a 64-bit format when the value is 1.

The timestamp_type_PTS information may indicate a presentation timestampaccording to a timestamp type of a timeline to be mapped, that is, apoint in time at which reproduction is performed. The timestamp_type_PTSinformation may be indicated by a 32-bit format when atimestamp_version_flag value is 0, and indicated by a 64-bit format whenthe value is 1. For example, when a timestamp_type field value indicatesNTP, a timestamp_type_PTS field value may have a timestamp value for anNTP-based reproduction time point.

The timestamp_type_DTS information may indicate a decoding timestampaccording to a timestamp type of a timeline to be mapped, that is, apoint in time at which decoding is performed. The timestamp_type_DTSinformation may be indicated by a 32-bit format when atimestamp_version_flag value is 0, and indicated by a 64-bit format whenthe value is 1. For example, when a timestamp_type field value indicatesan NTP, a timestamp_type_PTS field value may have a timestamp value foran NTPbased decoding time point.

FIG. 70 illustrates a scheme of synchronizing a stream transmittedthrough a heterogeneous network (for example, the Internet) with astream transmitted through the broadcasting network using a timelinecomponent when a timestamp of a broadcasting network transmission packetis absent according to an embodiment of the present invention.

In the above-described synchronization scheme through sharing of atimeline between transport streams transmitted through heterogeneousnetworks using the timeline component, the timeline may be shared bymapping a timestamp of a packet header of a broadcasting networktransport stream to a timestamp of an Internet transport stream includedin a timeline component AU of a packet payload on a one-to-one basis.

However, timestamp-related information may not be present in a header ofthe broadcasting network transmission packet.

As in the figure, when the timestamp-related information is not presentin the header of the transmission packet, additional information for anorigin timestamp in a timeline is needed. The timeline may be sharedbetween the broadcasting network and the Internet by mapping the origintimestamp to the timestamp of the Internet transport stream on aone-to-one basis.

Information related to the origin timestamp and the timestamp of thetransport stream in the heterogeneous network (for example, theInternet) may be included in the timeline component AU.

The origin timestamp may be defined as a timestamp on a referencetimeline. For example, in the above-described embodiment, a timestampfor the stream transmitted through the broadcasting network may bedefined as the origin timestamp.

The origin timestamp may represent a timeline reference value forconstituting a timeline of a stream transmitted over an internal network(e.g., the broadcast network).

FIG. 71 illustrates syntax of the timeline component AU according toanother embodiment of the present invention.

Syntax of the timeline component AU according to another embodiment ofthe present invention may include information related to the origintimestamp in addition to syntax of the timeline component AU describedabove.

The timeline component AU may include identifier information, versioninformation, AU_length information, location_flag information,origin_PTS_flag information, origin_DTS_flag information, origin_PTSinformation, origin_DTS information, location_length information,PTS_flag information, DTS_flag information, media_time_flag information,NTP_time_flag information, PTP_time_flag information, timecode_flaginformation, PCR_time_flag information, location_URL_length information,location_URL information, timescale information, media_time_PTSinformation, media_time_DTS information, NTP_time_PTS information,NTP_time_DTS information, PTP_time_PTS information, PTP_time_DTSinformation, timecode_PTS information, timecode_DTS information,PCR_time_PTS information, and/or PCR_time_DTS information.

Description of information corresponding to the same term as that of theinformation included in syntax of the timeline component AU describedabove is replaced by the above description.

The origin_PTS_flag information indicates whether the timeline componentAU includes an origin_PTS value.

The origin_DTS_flag information indicates whether the timeline componentAU includes an origin DTS value.

The origin_PTS information indicates a PTS of a current packet on areference base timeline of timeline mapping.

The origin_DTS information indicates a DTS of a current packet on areference base timeline of timeline mapping.

The location_URL_length information indicates a length of thelocation_URL information.

The location_URL information may indicate a URL of a stream transmittedthrough a heterogeneous network, or an identifier that uniquelyidentifies the stream transmitted through the heterogeneous network.

The receiver may acquire a timeline component AU from a packet payloadof a transport stream in the broadcasting network, and parse origin_PTSinformation and/or origin_DTS information in the timeline component AUto acquire timestamp information for the transport stream in thebroadcasting network based on the parsed information. The receiver maysynchronize a transport stream of the broadcasting network with atransport stream of a heterogeneous network using information related tothe timestamp of the transport stream in the broadcasting networkacquired through the origin_PTS information and/or the origin_DTSinformation and a timestamp for the heterogeneous network included inthe timeline component AU.

FIG. 72 illustrates syntax of the timeline component AU according toanother embodiment of the present invention.

The timeline component AU may include additional metadata related to amedia stream transmitted through the broadcasting network or theInternet. The figure illustrates the timeline component AU whichincludes metadata for a timeline related to the media stream among theadditional metadata.

The timeline component AU may be expressed in another format such asXML.

The timeline component AU may include identifier information, AU_lengthinformation, location_flag information, origin_timestamp_flaginformation, timestamp_version information, timestamp_type information,timestamp_format information, location_length information, locationinformation, origin_timestamp_version information, origin_timestamp_typeinformation, origin_timestamp_format information, origin_location_flaginformation, origin_location_length information, origin_locationinformation, origin_timescale information, origin_media_timeinformation, origin_timestamp information, private_data_lengthinformation, private_data_bytes( ) information, timescale information,media time information, timestamp information and/or data_bytes( )information.

Description of information corresponding to the same term as that of theinformation included in syntax of the timeline component AU describedabove is replaced by the above description.

The identifier information may be an identifier indicating that it ismetadata related to a timeline, or an identifier indicating that astructure of the timeline component AU is included.

The AU_length information may indicate a length of information includedin the timeline component AU.

The location_flag information may indicate whether location informationof a service, a content component, or the like related to informationincluded in the timeline component AU is included.

The origin_timestamp_flag information may indicate whether informationrelated to an origin timestamp is included.

The timestamp_version information may indicate version information of atimestamp included in the timeline component AU.

The timestamp_type information may indicate a type of a timestampincluded in the timeline component AU. For example, the timestamp_typeinformation may indicate a DTS that indicates a point in time at whichdata of an access unit or the like (for example, an audio access unit)of a related service/content component is decoded when thetimestamp_type information has a value of 0x00, and the timestamp_typeinformation may indicate a PTS that indicates a point in time at whichdata of an access unit or the like (for example, an audio access unit)of a related service/content component is reproduced when thetimestamp_type information has a value of 0x01.

The timestamp_format information may indicate a format of a timestampincluded in the timeline component AU. For example, the timestamp_formatinformation may indicate that the format is a media time when theinformation has a value of 0x00, an NTP when the information has a valueof 0x01, a PTP when the information has a value of 0x02, and a time codewhen the information has a value of 0x03. Values of 0x04-0x0F may bereserved for future extension.

The location_length information may indicate a length of a locationfield.

The location information may indicate location information of a service,a content component, or the like related to information included in thetimeline component AU. The location information may be expressed in aform such as an IP address/port number, a URI, or the like.

The origin_timestamp_version information may indicate a version of atimestamp format with respect to a base timeline that may serve as areference line of timeline mapping. It is possible to indicate that a32-bit format is used when a value of the corresponding field is 0, anda 64-bit format is used when the value is 1. For example, when a videostream is transmitted through the broadcasting network and an audiostream is transmitted through the Internet, and timeline mapping of theaudio stream to the video stream is performed, a timestamp of the videostream transmitted through the broadcasting network may correspond to areference base timeline. In this case, the origin_timestamp_versioninformation may indicate a timestamp format of the video streamtransmitted through the broadcasting network.

The origin_timestamp_type information may indicate a type of a timestampwith respect to a base timeline that may serve as a reference line oftimeline mapping. For example, the origin_timestamp_type information mayindicate a DTS that indicates a point in time at which data of an accessunit or the like (for example, an audio access unit) of aservice/content component or the like related to the base timeline isdecoded when the origin_timestamp_type information has a value of 0x00,and the origin_timestamp_type information may indicate a PTS thatindicates a point in time at which data of an access unit or the like(for example, an audio access unit) of a service/content component orthe like related to the base timeline is reproduced when theorigin_timestamp_type information has a value of 0x01.

The origin_timestamp_format information may indicate a format of atimestamp with respect to a base timeline that may serve as a referenceline of timeline mapping. For example, the origin_timestamp_formatinformation may indicate that the format is a media time when theinformation has a value of 0x00, an NTP when the information has a valueof 0x01, a PTP when the information has a value of 0x02, and a time codewhen the information has a value of 0x03. Values of 0x04-0x0F may bereserved for future extension.

The origin_location_flag information may indicate whether locationinformation of a service/content component or the like related to a basetimeline that may serve as a reference line of timeline mapping isincluded.

The origin_location_length information may indicate a length of anorigin_location field.

The origin_location information may indicate location information of aservice/content component or the like related to a base timeline thatmay serve as a reference line of timeline mapping. The origin_locationinformation may be expressed in a form such as an IP address/portnumber, a URI, or the like.

The origin_timescale information may indicate a timescale that may beused when expressing a media time of a base timeline that serves as areference line of timeline mapping. For example, in an MPEG-2 TS, thetimescale may have a value 90K.

The origin_media_time information may indicate a media time on a basetimeline that serves as a reference line of timeline mapping. Contentcontained in a corresponding media time may vary with anorigin_timestamp_type. For example, the origin_media_time informationmay indicate a media time with respect to a reproduction time point whenthe origin_timestamp_type is a PTS, and indicate a media time withrespect to a decoding time point when the origin_timestamp_type is aDTS. The origin_media_time information may be indicated by 32 bits whenan origin_timestamp_version value is 0 and by 64 bits when thecorresponding field value is 1.

The origin_timestamp information may indicate a timestamp of a formatthat varies with a field value of an origin_timestamp_format on a basetimeline serving as a reference line of timeline mapping, and contentcontained in a timestamp corresponding to the origin_timestampinformation may vary with the origin_timestamp_type. For example, whenthe origin_timestamp_type indicates DTS and a value of theorigin_timestamp_format is ‘0x01’, the timestamp corresponding to theorigin_timestamp information may indicate a decoding time pointexpressed by an NTP. The origin_timestamp information may be indicatedby 32 bits when the origin_timestamp_version is 0 and by 64 bits whenthe corresponding field value is 1.

The private_data_length information may indicate a length having a byteas a unit of the following private_data_bytes.

The private_data_bytes( ) information indicates an area which may beprivately defined to have a length corresponding to aprivate_data_length or include extended content later.

The timescale information may indicate a time scale available for usewhen expressing a media time.

The media_time information may indicate a media time. Content containedin a media time corresponding to the media_time information may varywith a timestamp_type. For example, when the timestamp_type is a PTS,the media_time information may indicate a media time with respect to areproduction time point. The media_time information may be indicated by32 bits when a timestamp_version value is 0 and by 64 bits when thecorresponding field value is 1.

The timestamp information may indicate a timestamp of a format thatvaries with a field value of a timestamp_format, and content containedin a timestamp corresponding to the timestamp information may vary witha timestamp_type. For example, when the timestamp_type indicates a DTSand the timestamp_format has a value ‘0x01’, the timestamp correspondingto the timestamp information may indicate a decoding time pointexpressed by an NTP. The timestamp information may be indicated by 32bits when a timestamp_version value is 0 and by 64 bits when thecorresponding field value is 1.

The data_bytes( ) information indicates fields or areas for includingextended content later.

FIG. 73 illustrates a method of synchronization between a streamtransmitted over a broadcast network and a stream transmitted over aheterogeneous network using timeline reference signaling informationaccording to another embodiment of the present invention.

As described above, when a video stream is transmitted over thebroadcast network and an audio stream is transmitted over the Internetnetwork, the two streams need to be synchronized for one service to bedecoded and/or reproduced. However, since the two streams have differenttimelines, a mechanism to map the two timelines to each other is needed.

According to another embodiment, at least one stream transmitted over aheterogeneous network such as the broadcast network and the Internetnetwork maybe synchronized using the timeline reference signalinginformation. That is, streams transmitted from the receiver of theaforementioned broadcast system over heterogeneous networks such as thebroadcast network and the Internet network may be synchronized and usedfor one service.

The transmitter according to another embodiment transmits informationenabling a stream transmitted over the broadcast network to besynchronized with a stream transmitted over the heterogeneous networkusing the timeline reference signaling information. To this end, thetransmitter of this embodiment may include a signaling encoder (notshown), a broadcast network interface (not shown), and/or aheterogeneous network interface (not shown).

The signaling encoder encodes timeline reference signaling informationcontaining metadata for synchronizing streams transmitted via one ormore networks.

The signaling encoder may include a first encoder for encoding abroadcast stream including a first portion (e.g., video information) ofthe broadcast content and the timeline reference signaling informationand a second encoder for encoding a heterogeneous stream including asecond portion (e.g., audio information) of the broadcast content.

The timeline reference signaling information may include at least onetimeline reference information constituting timeline of at least one ofthe broadcast stream and the heterogeneous stream.

The broadcast network interface may transmit the encoded broadcaststream via a broadcast network.

The heterogeneous network interface may transmit the encodedheterogeneous stream via a heterogeneous network.

In addition, the receiver according to another embodiment maysynchronize a stream transmitted via the broadcast network with a streamtransmitted via a heterogeneous network using the timeline referencesignaling information. To this end, the receiver of this embodiment mayinclude a broadcast network interface (not shown), a heterogeneousnetwork interface (not shown), and/or a processor (not shown).

The broadcast network interface may receive a broadcast stream includinga first portion (e.g., video information) of the broadcast content via abroadcast network. The broadcast network interface may include thebroadcast interface J2030 and/or the transport packet interface J32070as described above.

The heterogeneous network interface may receive a heterogeneous streamincluding a second portion (e.g., audio information) of the broadcastcontent via a heterogeneous network. The heterogeneous network interfacemay include the Internet interface J2020 and/or the broadband packetinterface J32080 as described above.

The broadcast stream may include timeline reference signalinginformation containing metadata for synchronizing streams transmittedvia the one or more networks. The timeline reference signalinginformation may include at least one timeline reference informationconstituting a timeline of at least one of the broadcast stream and theheterogeneous stream.

The processor may configure the broadcast content using the broadcaststream and the heterogeneous stream based on the timeline referencesignaling information. The processor may include the processor J2080and/or the A/V processor J32110 described above.

The broadcast stream according to another embodiment may include apacket header and/or a packet payload. The packet header may include atimestamp for the broadcast stream. The packet payload may include thetimeline reference signaling information. However, embodiments of thepresent invention are not limited thereto. The timeline referencesignaling information may be included in the packet header.

When the timeline reference signaling information is included in thepacket payload and transmitted, the timeline reference signalinginformation may be included in a timeline reference information AU(access unit). A timeline component AU may include the timelinereference information AU. However, embodiments of the present inventionare not limited thereto. The timeline reference information AU may bepresent independently of the timeline component AU.

In the case in which the timeline reference signaling information isincluded in the packet header, timeline reference signaling informationmay be included in an extended header extension.

The timeline component AU and/or timeline reference information AUtransmitted via the broadcast network may include internal timelinereference information constituting timeline of a stream transmitted viathe broadcast network, which is an internal network, and/or externaltimeline reference information capable of mapping the timeline of astream transmitted via the heterogeneous network (e.g., Internetnetwork), which is an external network to the internal network.

The timestamp described above represents a time to start decoding suchas a DTS and/or a PTS and/or a time to start presentation. Accordingly,the timestamp indicates only times such as the decoding time and thepresentation time at which a specific event occurs.

The timeline reference information according to another embodimentrepresents a reference clock value constituting the timeline of a mediastream transmitted over the internal network and/or the externalnetwork. Herein, the reference clock value represents time informationindicating a time constituting the timeline of the media stream. Herein,the time constituting the timeline may correspond to a predeterminedtime in a broadcast system. For example, the reference clock value mayinclude timestamp information such as DTS and PTS and/or a wall clock.However, the reference clock value is not limited to the DTS and/or thePTS.

In addition, the timeline reference information AU may be packetized inthe form of a packet structure identical to that of a broadcast networktransmission stream.

According to another embodiment of the present invention, the receivermay synchronize two streams transmitted via the broadcast network andthe heterogeneous network (e.g., the Internet network) on one timelinebased on the timeline reference information AU, thereby decoding and/orreproducing the same. For example, the receiver and/or the processor mayconfigure broadcast content using the broadcast stream and theheterogeneous stream based on the timestamps and/or the timelinereference signaling information. The receiver and/or the processor maymap a stream transmitted via the broadcast network to a streamtransmitted via the heterogeneous network based on the internal timelinereference information and the external timeline reference information.In the case in which the external timeline reference informationincludes timestamp information such as DTS and/or PTS, the receiverand/or the processor may map the stream transmitted via the broadcastnetwork to the stream transmitted via the heterogeneous network based onthe external timeline reference information and the timestampinformation constituting the timeline of a media stream transmitted overthe internal network.

The description given above may also be applied to a case in whichstreams transmitted via one network use different timelines. Forexample, when a heterogeneous stream corresponds to a broadcast stream,the timeline of the heterogeneous stream may differ from that of thebroadcast stream.

With the method described above, a relay service operator collecting thestreams transmitted via a plurality of heterogeneous networks andproviding the same to viewers need not directly perform reprocessing forsynchronization of the different streams.

FIG. 74 illustrates a syntax of a timeline reference information AUaccording to another embodiment of the present invention.

The timeline reference information AU may be presented in other formatssuch as XML. The timeline reference information AU may be applied tovarious media transmission protocols such as RPT and ALC/LCT, and usedby being operatively connected with service signaling information properfor the protocols.

The service signaling information may include information such asinformation indicating that a stream is carrying a timeline reference ofan internal network or an external network, external media URLinformation contained in the timeline reference information AU, flaginformation indicating whether various fields are included, and/ortimescale information which are applicable to each packet in common.

Specifically, the timeline reference information AU may includeAU_identifier information, AU_length information,external_media_URL_flag information, internal_timeline_reference_flaginformation, external_timeline_reference_flag information,external_media_URL_length information, external_media_URL information,internal_timeline_reference_format information,internal_timeline_reference_timescale_flag information,internal_timeline_reference_length information,internal_timeline_reference_timescale information,internal_timeline_reference information,external_timeline_reference_format information,external_timeline_reference_timescale_flag information,external_timeline_reference_length information,external_timeline_reference_timescale information, and/orexternal_timeline_reference information. The information which thetimeline reference information AU includes may be referred to astimeline reference signaling information.

Description of the information included in the syntax of the timelinecomponent AU described above may be applied to the information assignedthe same names.

The AU_identifier information is an identifier uniquely representing thestructure of the timeline reference information AU.

The AU_length information indicates the length of a timeline referenceinformation AU.

The external_media_URL_flag information indicates whether or not thetimeline reference information AU includes URL information of a streamtransmitted via an external network (e.g., the Internet network).

The internal_timeline_reference_flag information indicates whether notthe timeline reference information AU includes internal timelinereference information.

The external_timeline_reference_flag information indicates whether ornot the timeline reference information AU includes external timelinereference information.

The external_media_URL_length information indicates the length of theexternal media URL information. For example, theexternal_media_URL_length information may indicate the length of theexternal media URL information in bytes.

The external_media_URL information may include such information aslocation information about media transmitted via an external network(e.g., the Internet network), and/or a unique identifier (identificationinformation). For example, if the media transmitted over the externalnetwork is MPEG-DASH, the external_media_URL information may include aURL of the corresponding MPD and/or MPD ID.

The internal_timeline reference_format information may indicate theformat of the internal timeline reference. For example, if the value ofthe internal_timeline_reference_format information is 0x00, this mayindicate that the format is the media time. If the value is 0x01, thismay indicate that the format is the network time protocol (NTP). If thevalue is 0x02, this may indicate that the format is PTP. If the value is0x03, this may indicate that the format is the timecode. If the value isone of 0x04 to 0x1F, it may be reserved such that the format can bedefined later.

The internal_timeline_reference_timescale_flag information indicateswhether or not the timeline reference information AU contains atimescale about the internal timeline reference.

The internal_timeline_reference_length information indicates the lengthof the internal timeline reference value. For example, theinternal_timeline_reference_length information may indicate the lengthof the internal timeline reference value in bytes.

The internal_timeline_reference_timescale information indicates the timeunit of the internal timeline reference information. For example, theinternal_timeline_reference_timescale information may indicate the timeunit of the internal timeline reference value in Hz.

The internal_timeline_reference information indicates a reference clockvalue constituting the timeline of a media stream transmitted over theinternal network.

The external_timeline_reference_format information may indicate theformat of the external timeline reference. For example, if the value ofthe external_timeline_reference_format information 0x00, this mayindicate the media time. If the values is 0x01, this may indicate thenetwork time protocol (NTP). If the value is 0x02, this may indicatePTP. If the value is 0x03, this may indicate the timecode. If the valueis one of 0x04 to 0x1F, it may be reserved such that the format can bedefined later.

The external_timeline_reference_timescale_flag information indicateswhether or not the timeline reference information AU contains atimescale of the external timeline reference.

The external_timeline_reference_length information indicates the lengthof the external timeline reference value. For example, theexternal_timeline_reference_length information may indicate the lengthof the external timeline reference value in bytes.

The external_timeline_reference_timescale information indicates the timeunit of the external timeline reference information. For example, theexternal_timeline_reference_timescale information may indicate the timeunit of the external timeline reference value in Hz.

The external timeline reference information indicates a reference clockvalue constituting the timeline of a media stream transmitted over anexternal network.

According to another embodiment of the present invention, the receiverand/or the processor may synchronize a stream transmitted over thebroadcast network with a stream transmitted over a heterogeneous networkby applying the internal_timeline_reference information and/orexternal_timeline_reference information which are included in thetimeline reference information AU and/or the timeline component AU tothe stream of the external network identified by the external_media_URLinformation. In addition, the receiver and/or the processor mayconfigure broadcast content using the broadcast stream and theheterogeneous stream based on the external media URL information, thetimeline reference information, and/or the timestamps.

FIG. 75 illustrates a syntax of a timeline reference information AUaccording to another embodiment of the present invention.

The timeline reference information AU of this embodiment may include atleast one piece (or multiple pieces) of internal_timeline_referenceinformation. In addition, the timeline reference information AU mayinclude at least one (or multiple) external timeline referenceinformation.

Specifically, the timeline reference information AU may includeAU_identifier information, AU_length information,external_media_location_flag information, nb_of_timeline_referenceinformation, external_media_URL_length information, external_media_URLinformation, timeline_reference_type information,timeline_reference_identifier information, timeline_reference_formatinformation, timeline_reference_timescale_flag information,timeline_reference_length information, timeline_reference_timescaleinformation, and/or timeline reference information. The informationincluded in the timeline reference information AU may be referred to astimeline reference signaling information.

Description of the information included in the syntax of the timelinereference information AU described above may be applied to theinformation assigned the same names.

The AU_identifier information is an identifier uniquely representing thestructure of the timeline reference information AU.

The AU_length information indicates the length of a timeline referenceinformation AU.

The external_media_URL_flag information indicates whether or not thetimeline reference information AU includes URL information of a streamtransmitted via an external network (e.g., the Internet network).

The nb_of_timeline_reference information indicates the number oftimeline reference informations included in the timeline referenceinformation AU.

The external_media_URL_length information indicates the length of theexternal media URL information. For example, the external_mediaURL_length information may indicate the length of the external media URLinformation in bytes.

The external_media_URL information may include such information aslocation information about media transmitted via an external network(e.g., the Internet network), and/or a unique identifier. For example,if the media transmitted over the external network is MPEG-DASH, theexternal_media_URL information may include may include a URL of thecorresponding MPD, and/or MPD ID.

The timeline_reference_type information indicates the type of thetimeline reference information. For example, if thetimeline_reference_type information is set to ‘0’, the type of thetimeline reference information may indicate internal timeline referenceinformation. If the timeline_reference_type information is set to ‘1’,the type of the timeline reference information may indicate externaltimeline reference information.

The timeline_reference_identifier information is a unique identifier ofthe timeline reference information. For example, thetimeline_reference_identifier information may be assigned an integervalue between 0 and 127.

The timeline_reference_format information may indicate the format of theinternal timeline reference information and/or the format of theexternal timeline reference information. For example, if the value ofthe timeline_reference_format information is 0x00, this may indicatethat the format is the media time. If the value is 0x01, this mayindicate that the format is the network time protocol (NTP). If thevalue is 0x02, this may indicate that the format is PTP. If the value is0x03, this may indicate that the format is the timecode. If the value isone of 0x04 to 0x1F, it may be reserved such that the format can bedefined later.

The timeline_reference_timescale_flag information indicates whether ornot the timeline reference information AU contains timescale informationabout the internal timeline reference information and/or the externaltimeline reference information.

The timeline_reference_length information indicates the length of theinternal timeline reference value and/or the length of the externaltimeline reference value. For example, the timeline_reference_lengthinformation may indicate the length of the internal timeline referencevalue and/or the length of the external timeline reference value inbytes.

The timeline_reference_timescale information indicates the time unit ofthe internal timeline reference value and/or the time unit of theexternal timeline reference value. For example, thetimeline_reference_timescale information may indicate the time unit ofthe internal timeline reference value and/or the time unit of theexternal timeline reference value in Hz.

The timeline_reference information indicates a reference clock valueconstituting the timeline of a media stream transmitted over an internalnetwork and/or an external network. For example, the timeline referenceinformation may have at least one value (or multiple values) based onthe nb_of_timeline_reference information. The timeline_referenceinformation may include at least one internal_timeline_informationand/or at least one external_timeline_reference information describedabove.

According to another embodiment of the present invention, the receivermay synchronize a stream transmitted over the broadcast network with astream transmitted over a heterogeneous network by applying at least onetimeline reference information included in the timeline component AUand/or the timeline reference information AU to the stream of theexternal network identified by the external_media_URL information.Specifically, the receiver may synchronize a stream transmitted over thebroadcast network with a stream transmitted over a heterogeneous networkby applying at least one (or multiple) internal_time_referenceinformation and/or at least one (multiple) external_timeline_referenceinformation included in the timeline component AU and/or the timelinereference information AU to the stream of the external networkidentified by the external_media_URL information.

FIG. 76 illustrates the structure of an LCT packet supportingtransmission of timeline reference information according to anotherembodiment of the present invention.

A broadcast stream according to this embodiment may include an LCTpacket. The timeline reference signaling information of this embodimentmay be transmitted by being included in an extended Header Extension.For example, the LCT packet may include the timeline reference signalinginformation by extending the existing header extension (EXT_TIME).According to this embodiment, the timeline reference signalinginformation is information for synchronization of media streamstransmitted over heterogeneous networks. The timeline referencesignaling information may include information identical and/or similarto the timeline reference information AU described above. The timelinereference signaling information may be applied to a packet for atransmission protocol such as the real-time protocol (RTP).

The timeline reference signaling information may operate in connectionwith service signaling information proper for the aforementionedprotocol. The service signaling information may include information suchas information indicating that a stream is carrying a timeline referenceof an internal network or an external network, external media URLinformation contained in the timeline reference information AU, flaginformation, and/or timescale information which are applicable to eachpacket in common.

A packet according to another embodiment may be an LCT packet. The LCTpacket may include an LCT version number field (V), a congestion controlflag field (C), a Protocol-Specific Indication field (PSI), a TransportSession Identifier flag field (S), a Transport Object Identifier flagfield (O), a Half-word flag field (H), a Reserved field (Res), a CloseSession flag field (A), a Close Object flag field (B), an LCT headerlength field (HDR_LEN), a Codepoint field (CP), a Congestion ControlInformation field (CCI), a Transport Session Identifier field (TSI), aTransport Object Identifier field (TOI), a Header Extensions field, anFEC Payload ID field, and/or an Encoding Symbol(s) field.

LCT version number field (V) indicates the protocol version number. Forexample, this field indicates the LCT version number. The version numberfield of the LCT header may be interpreted as the ROUTE version numberfield. This version of ROUTE implicitly makes use of version ‘1’ of theLCT building block. For example, the version number is ‘0001b’.

The congestion control flag field (C) indicates the length of aCongestion Control Information field. C=0 indicates that the CongestionControl Information (CCI) field is 32-bits in length. C=1 indicates thatthe CCI field is 64-bits in length. C=2 indicates that the CCI field is96-bits in length. C=3 indicates that the CCI field is 128-bits inlength.

The Protocol-Specific Indication field (PSI) may be used as an indicatorfor a specific purpose in an LCT higher protocol. The PSI fieldindicates whether the current packet is a source packet or an FEC repairpacket. As the ROUTE source protocol only delivers source packets, thisfield shall be set to ‘10b’. Transport Session Identifier flag field(S)indicates the length of a Transport Session Identifier field.

The Transport Object Identifier flag field (O) indicates the length of aTransport Object Identifier field. For example, an object may representone file, and the TOI is identification information about each object. Afile with the TOI set to 0 is referred to as FDT.

The Half-word flag field (H) indicates whether or not a half-word (16bits) is added to the length of the TSI and TOI fields.

Reserved field (Res) reserved for future use.

The Close Session flag field (A) indicates that a session closes or isabout to close.

The Close Object flag field (B) indicates that an object beingtransmitted closes or is about to close.

The LCT header length field (HDR_LEN) indicates the total length of theLCT header in units of 32-bit words.

The Codepoint field (CP) indicates the type of the payload that iscarried by this packet. Depending on the type of the payload, additionalpayload header may be added to prefix the payload data.

The Congestion Control Information field (CCI) is used in transmittingCongestion Control information such as layer numbers, logical channelnumbers, and sequence numbers. The Congestion Control Information fieldin the LCT header contains the required Congestion Control Information.

The Transport Session Identifier field (TSI) is a unique identifier of asession. The TSI uniquely identifies a session among all sessions from aparticular sender. Each TSI field may be mapped to each component and/orrepresentation of MPEG-DASH.

This field identifies the Transport Session in ROUTE. The context of theTransport Session is provided by the LSID (LCT Session Instancedescription). The LSID defines what is carried in each constituent LCTtransport session of the ROUTE session. Each transport session isuniquely identified by a Transport Session Identifier (TSI) in the LCTheader. The LSID may be transmitted through the same ROUTE sessionincluding LCT transport sessions, or may be transmitted via acommunication network, a broadcast network, an Internet network, a cablenetwork, and/or a satellite network. Means for transmission of the LSIDare not limited thereto. For example, the LSID may be transmittedthrough a specific LCT transport session with the value of TSI set to‘0’. The LSID may include signaling information about all transportsessions transmitted through the ROUTE session. The LSID may includeLSID version information and information about validity of the LSID. TheLSID may also include transport session information providinginformation about the LCT transport session. The transport sessioninformation may include TSI information for identifying a transportsession, source flow information transmitted to a corresponding TSI andproviding information about a source flow through which source data istransmitted, repair flow information transmitted to a corresponding TSIand providing information about a repair flow through which repair datais transmitted, and transport session property information includingadditional property information about the transport session.

The Transport Object Identifier field (TOI) is a unique identifier of anobject. The TOI indicates which object within the session this packetpertains to. Each TOI field may be mapped to each segment of MPEG-DASH.However, embodiments of the present invention are not limited thereto.Each TOI field may be mapped to a part of a segment of MPEG-DASH such asChunk, GOP, and/or Access Unit.

This field indicates to which object within this session the payload ofthe current packet belongs. The mapping of the TOI field to the objectis provided by the Extended FDT. Extended FDT specifies the details ofthe file delivery data. This is the extended FDT instance. The extendedFDT together with the LCT packet header may be used to generate theFDT-equivalent descriptions for the delivery object. The Extended FDTmay either be embedded or may be provided as a reference. If provided asa reference the Extended FDT may be updated independently of the LSID.If referenced, it shall be delivered as an in-band object on TOI=0 ofthe included source flow.

The Header Extensions field is used as an LCT header extension part fortransmission of additional information. The Header Extensions are usedin LCT to accommodate optional header fields that are not always used orhave variable size.

For example, EXT_TIME extension is used to carry several types of timinginformation. It includes general purpose timing information, namely theSender Current Time (SCT), Expected Residual Time (ERT), and Sender LastChange (SLC) time extensions described in the present document.

The FEC Payload ID field includes identification information about anencoding symbol or a transmission block. FEC Payload ID indicates anidentifier for a case in which the file is FEC-encoded. For example,when the FLUTE protocol file is FECencoded, an FEC Payload ID may beallocated in order for a broadcasting station or a broadcasting serverto identify the file.

The Encoding Symbol(s) field may include data of a transmission block oran encoding symbol.

The packet payload contains bytes generated from an object. If more thanone object is carried in the session, then the Transmission Object ID(TOI) within the LCT header MUST be used to identify from which objectthe packet payload data is generated.

Header Extensions (EXT_TIME) according to another embodiment may includea Header Extension Type field (HET), a Header Extension Length field(HEL), an SCT Hi field, an SCT Low field, an ERT field, an SLC field, aReserved field, a Sender Current Time field, an Expected Residual Timefield, and/or a Session Last Changed field. Header Extensions (EXT_TIME)may also include a Use field. The Use field may include an SCT Hi field,an SCT Low field, an ERT field, an SLC field, and/or a Reserved field.

The Header Extension Type field (HET) indicates the type of acorresponding Header Extension. The HET field may be an 8-bit integer.Basically, in LCT, if HET has a value between 0 and 127, HeaderExtension with a variable length in the unit of 32-bit word is presentin HET, and the length thereof is described in Header Extension Lengthfield (HEL) subsequent to HET. If HET has a value between 128 and 255,the Header Extension has a 32-bit fixed length. For example, the HETfield may have ‘2’ or a value less than or equal to ‘127’ and identifyHeader Extension described above.

The HEL field indicates the total length of Header Extension with avariable length. Basically, in LCT, if HET has a value between 0 and127, Header Extension with a variable length in the unit of 32-bit wordis present in HET, and the HEL field subsequent to the HET fieldindicates the total length of Header Extension in the unit of 32-bitword.

The Use field (Use) indicates the semantic of the following 32-bit timevalue(s).

The SCT Hi field indicates whether or not a Sender Current Time field isincluded in the header extension.

The SCT Low field indicates whether or not a 64-bit Sender Current Timefield is included in the header extension.

The ERT field indicates whether or not an Expected Residual Time fieldis included in the header extension.

The SLC field indicates whether or not a Session Last Changed field isincluded in the header extension.

The Reserved field (Res) is reserved for future use.

The Sender Current Time field represents the current clock at the senderand at the time this packet was transmitted, measured in units of 1 msand computed modulo 2̂32 units from the start of the session.

When the SCT High field is set, the associated 32-bit time valueprovides an unsigned integer representing the time in seconds of thesender's wall clock. In the particular case where NTP is used, these 32bits provide an unsigned integer representing the time in secondsrelative to 00:00 hours GMT, Jan. 1 1900, (i.e., the most significant 32bits of a full 64-bit NTP time value).

When the SCT-Low flag is set, the associated 32-bit time value providesan unsigned integer representing a multiple of ½̂̂32 of a second, in orderto allow sub-second precision. When the SCT-Low flag is set, theSCT-High flag MUST be set, too. In the particular case where NTP isused, these 32 bits provide the 32 least significant bits of a 64-bitNTP timestamp.

Expected Residual Time field represents the sender expected residualtransmission time for the current session or for transmission of thecurrent object, measured in units of 1 ms. If the packet containing theERT field also contains the TOI field, then ERT refers to the objectcorresponding to the TOI field, otherwise it refers to the session.

If the packet containing the ERT timing information also contains theTOI field, then ERT refers to the object corresponding to the TOI field;otherwise, it refers to the only object in the session. When the ERTflag is set, it is expressed as a number of seconds. The 32 bits providean unsigned integer representing this number of seconds.

Session Last Changed field represents the server wall clock time, inseconds, at which the last change to session data occurred. That is, itexpresses the time at which the last (most recent) Transport Objectaddition, modification, or removal was made for the delivery session. Inthe case of modifications and additions, it indicates that new data willbe transported that was not transported prior to this time. In the caseof removals, SLC indicates that some prior data will no longer betransported. When the SLC field is set, the associated 32-bit time valueprovides an unsigned integer representing a time in seconds. In theparticular case where NTP is used, these 32 bits provide an unsignedinteger representing the time in seconds relative to 00:00 hours GMT,Jan. 1 1900, (i.e., the most significant 32 bits of a full 64-bit NTPtime value). In that case, handling of wraparound of the 32-bit time isoutside the scope of NTP and LCT. In some cases, it may be appropriatethat a packet containing an EXT_TIME Header Extension with SLCinformation also contain an SCT-High information.

The LCT packet may further include the timeline reference signalinginformation (internal_timeline_reference information and/orexternal_timeline_reference information) described above by extendingthe Header Extensions (EXT_TIME).

The timeline reference signaling information may include ITR Hiinformation, ITR Low information, ETR Hi information, ETR Lowinformation, internal_timeline_reference_timescale_flag information (ITRScale), external_timeline_reference_timescale_flag information (ETRScale), internal_timeline_reference_format information (ITR Format),external_timeline_reference_format information (ETR Format),external_media_URL_flag information (URL), internal_timeline_referenceinformation (Internal Timeline Reference), external_timeline_referenceinformation (External Timeline Reference),internal_timeline_reference_timescale information (Internal TimelineReference Timescale), external_timeline_reference_timescale information(External Timeline Reference Timescale), and/or external_media_URLinformation (External Media URL).

Header Extensions (EXT_TIME) may include Use information. The Useinformation may include ITR Hi information, ITR Low information, ETR Hiinformation, ETR Low information,internal_timeline_reference_timescale_flag information (ITR Scale),external_timeline_reference_timescale_flag information (ETR Scale),internal_timeline_reference_format information (ITR Format),external_timeline_reference_format information (ETR Format), and/orexternal_media_URL_flag information (URL).

The ITR Hi information and/or the ITR Low information may be referred toas the internal_timeline_reference_flag information described above. TheETR Hi information and/or the ETR Low information may be referred to asthe external_timeline_reference_flag information described above.

The ITR Hi (Internal Timeline Reference High Flag) information indicateswhether or not 64-bit internal_timeline_reference information (InternalTimeline Reference) is included in the header extension.

The ITR Low (Internal Timeline Reference Low Flag) information indicateswhether or not 32-bit internal_timeline_reference information (InternalTimeline Reference) is included in the header extension.

The ETR Hi (External Timeline Reference High Flag) information indicateswhether or not 64-bit external_timeline_reference information isincluded in the header extension.

The ETR Low (External Timeline Reference Low Flag) information indicateswhether or not 32-bit external_timeline_reference information isincluded in the header extension.

The internal_timeline_reference_timescale_flag information (ITR Scale)indicates whether or not 32-bit internal_timeline_reference_timescaleinformation is included in the header extension.

The external_timeline_reference_timescale_flag information (ETR Scale)indicates whether or not 32-bit external_timeline_reference_timescaleinformation is included in the header extension.

The internal_timeline_reference_format information (ITR Format) mayindicate the format of an internal timeline reference. For example, ifthe value of the internal_timeline_reference_format information (ITRFormat) is 0x00, this may indicate that the format is the media time. Ifthe value is 0x01, this may indicate that the format is the network timeprotocol (NTP). If the value is 0x02, this may indicate that the formatis PTP. If the value is 0x03, this may indicate that the format is thetimecode. If the value is one of 0x04 to 0x1F, it may be reserved suchthat the format can be defined later.

The external_timeline_reference_format information (ETR Format) mayindicate the format of an external timeline reference. For example, ifthe value of the external_timeline_reference_format information (ETRFormat) is 0x00, this may indicate that the format is the media time. Ifthe value is 0x01, this may indicate that the format is the network timeprotocol (NTP). If the value is 0x02, this may indicate that the formatis PTP. If the value is 0x03, this may indicate that the format is thetimecode. If the value is one of 0x04 to 0x1F, it may be reserved suchthat the format can be defined later.

The external_media_URL_flag information (URL) may indicate whether ornot the external_media_URL information (External Media URL) is includedin the header extension.

The internal_timeline_reference information (Internal TimelineReference) indicates a reference clock value constituting the timelineof a media stream transmitted over the Internal network.

The external_timeline_reference information (External TimelineReference) is a reference clock value constituting the timeline of amedia stream transmitted over an external network.

The internal_timeline_reference_timescale information (Internal TimelineReference Timescale) indicates the time unit of internal timelinereference information. For example, theinternal_timeline_reference_timescale information may indicate the timeunit of the internal timeline reference value in Hz.

The external_timeline_reference_timescale information (External TimelineReference Timescale) indicates the time unit of external timelinereference information. For example, theexternal_timeline_reference_timescale information may indicate the timeunit of the external timeline reference value in Hz.

The external_media_URL information (External Media URL) may includeinformation such as location information about media transmitted via anexternal network (e.g., the Internet network), and/or a uniqueidentifier. For example, if the media transmitted over the externalnetwork is MPEG-DASH, the external_media_URL information may includeinformation such as URL of the corresponding MPD and/or MPD ID. Thelength of this field may be identified through the HEL field.

According to another embodiment of the present invention, the receiverand/or the processor may acquire LCT Header Extensions (EXT_TIME) frombroadcast signals of the broadcast network and acquire the timelinereference signaling information from the Header Extensions (EXT_TIME).In addition, the receiver and/or the processor may synchronize a streamtransmitted via the broadcast network with a stream transmitted via aheterogeneous network by applying timestamps,internal_timeline_reference information, and/or external timelinereference information to a stream of an external network identified bythe external_media_URL information.

FIG. 77 illustrates the structure of an LCT packet supportingtransmission of timeline reference information according to anotherembodiment of the present invention.

The LCT packet of this embodiment may include timeline referencesignaling information (EXT_TRC (Extension for Timeline Reference Clock))by extending the existing Header Extension. The timeline referencesignaling information may include information identical and/or similarto the timeline reference information AU described above. The timelinereference signaling information may be applied to a packet for atransmission protocol such as the real-time protocol (RTP).

The timeline reference signaling information may operate in connectionwith service signaling information proper for the aforementionedprotocol. The service signaling information may include information suchas information indicating that a stream is carrying a timeline referenceof an internal network or an external network, external media URLinformation contained in the timeline reference information AU, flaginformation, and/or timescale information which are applicable to eachpacket in common.

A packet according to another embodiment may be an LCT packet. The LCTpacket may include an LCT version number field (V), a congestion controlflag field (C), a Protocol-Specific Indication field (PSI), a TransportSession Identifier flag field (S), a Transport Object Identifier flagfield (O), a Half-word flag field (H), a Reserved field (Res), a CloseSession flag field (A), a Close Object flag field (B), an LCT headerlength field (HDR_LEN), a Codepoint field (CP), a Congestion ControlInformation field (CCI), a Transport Session Identifier field (TSI), aTransport Object Identifier field (TOI), a Header Extensions field, anFEC Payload ID field, and/or an Encoding Symbol(s) field.

The LCT packet may further include the timeline reference signalinginformation described above by extending the existing Header Extensions(EXT_TRC (Extension for Timeline Reference Clock)).

The timeline reference signaling information may include ITR Hiinformation, ITR Low information, ETR Hi information, ETR Lowinformation, internal_timeline_reference_timescale_flag information (ITRScale), external_timeline_reference_timescale_flag information (ETRScale), external_media_URL_flag information (URL), Reserved information(Res), internal timeline_reference_format information (ITR Format),external_timeline_reference_format information (ETR Format),internal_timeline_reference information (Internal Timeline Reference),external_timeline_reference information (External Timeline Reference),internal_timeline_reference_timescale information (Internal TimelineReference Timescale), external_timeline_reference_timescale information(External Timeline Reference Timescale), and/or external_media_URLinformation (External Media URL).

Header Extensions (EXT_TIME) may include Use information. The Useinformation may include ITR Hi information, ITR Low information, ETR Hiinformation, ETR Low information,internal_timeline_reference_timescale_flag information (ITR Scale),external_timeline_reference_timescale_flag information (ETR Scale),external_media_URL_flag information (URL), Reserved information (Res),internal_timeline_reference_format information (ITR Format), and/orexternal_timeline_reference_format information (ETR Format).

Description of the information included in the LCT packet describedabove is applied to the information assigned the same names.

According to another embodiment of the present invention, the receiverand/or the processor may acquire Header Extensions (EXT_TIME) frombroadcast signals of the broadcast network and acquire the timelinereference signaling information from the Header Extensions (EXT_TIME).In addition, the receiver and/or the processor may synchronize a streamtransmitted via the broadcast network with a stream transmitted via aheterogeneous network by applying timestamps,internal_timeline_reference information, and/orexternal_timeline_reference information to a stream of an externalnetwork identified by the the external media URL information.

FIG. 78 illustrates a synchronization scheme using the timelinecomponent AU between a transport stream in the broadcasting network towhich DASH is applied and a transport stream in a heterogeneous network(for example, the Internet) according to an embodiment of the presentinvention.

This figure illustrates an example in which a synchronization schemebetween transport streams through heterogeneous networks is applied toDASH using a timeline component. In this example, a video stream may betransmitted through the broadcasting network, and an audio stream may betransmitted through the Internet. Even though both the streams areserviced by being encapsulated through DASH, the streams are transmittedthrough separate networks and thus may have different timelines asseparate forms of content having separate MPDs.

To synchronize the two streams having separate timelines, the timelinecomponent may be included in DASH content transmitted through thebroadcasting network. The video stream transmitted through thebroadcasting network and a timeline component stream may be included inone content to share one timeline. The timeline component includestimeline information of the audio stream transmitted through theInternet. The receiver may synchronize the transport stream in theInternet through a timeline of the broadcasting network based on thisinformation.

The timeline component stream may be configured as one track similarlyto the video stream or the audio stream in the DASH content. Thetimeline component stream may be assigned a timestamp such as a DTS, aPTS, or the like with an AU as a unit using timing information providedby MPD and traf boxes and the like, and mapped to a broadcasting networktimeline. When the timeline component stream is configured as the track,signaling information may be needed to verify that the track includesthe timeline component stream. The signaling information may be includedin an hdlr box in an ISO BMFF-based DASH initialization segment, andprovided as a handler_type that indicates a type of included media, asample entry in an stsd box indicating initialization information and aspecific type of a media stream and a media header box included in anminf box, and the like.

The timeline component may be indicated to be included in a metadatatype by a handler type of “meta” in the hdlr box, and include a nullmedia header box referred to as “nmhd”.

FIG. 79 illustrates the sample entry for identifying a timelinecomponent in the ISO BMFF according to an embodiment of the presentinvention.

According to the present embodiment, stream signaling informationincluded in the stsd box may be configured as illustrated to identifythe timeline component.

To identify a timeline component stream in a file, Timeline ComponentMetaData SampleEntry may be defined as a derived type of a metadatasample entry. Timeline Component MetaData SampleEntry may have a 4-bytetype such as ‘mete’, and be uniquely identified in a file using theabove-mentioned type field.

A location URL of a stream described by the timeline component orparameters for signaling and initialization such as an initial delayoccurring until the stream is reproduced may be included in an “mete”sample entry.

FIG. 80 illustrates a track reference type box for expressing adependency relation between a timeline component track and another trackin the ISO BMFF according to an embodiment of the present invention.

To include the timeline component in an ISO BMFF-based file structuresuch as a DASH segment, it is possible to signal information about thedependency relation with respect to another track in addition to theabove-described signaling information. This figure illustrates anexample in which a dependency relation between the timeline componenttrack and another track of the DASH segment is expressed through a trefbox that expresses a dependency relation between tracks.

The tref box includes the track reference type box therein. The tref boxmay define a reference_type referred to as ‘metl’ as described above asa type for expressing a dependency relation between the above-describedtimeline component and another track. A track_ID in the tref boxindicates an ID of a track having a reference relation. It is possibleto express a dependency relation between the timeline component trackand another track that shares a timeline with the timeline componenttrack by defining the ‘metl’ reference type box.

As illustrated in the figure described above, the tref box including theabovedescribed ‘metl’ box is included in a timeline component track box,and includes an ID of a video track having a dependency relation in the‘metl’ box. Alternatively, the tref box and the ‘metl’ box may beincluded in the video track of the example, and a track_ID of ‘metl’ mayinclude an ID of the timeline component track.

FIG. 81 illustrates a configuration for acquiring a service and/orcontent in the next generation broadcasting system according to anembodiment of the present invention.

The scheme proposed in the present invention enables the receiver toefficiently acquire a service or content through the broadcastingnetwork or the Internet in the next generation broadcasting system.

The figure illustrates an example for acquisition of a service orcontent in a hybrid broadcasting system.

For example, Service 0 includes one video and one audio, and eachvideo/audio may be acquired through an IP stream transmitted through aterrestrial broadcasting network.

In Service 1, an IP stream for transmitting a video and an IP stream fortransmitting audio are transmitted through one PLP and thus the receivermay acquire Service 1 by decoding the PLP.

In Service N, while video is transmitted through the terrestrialbroadcasting network, audio may be acquired through the Internet.

As described in the foregoing, the above-described embodiments of thepresent invention may be used when the receiver acquires a componentincluded in Service 0, Service 1 or Service N. That is, the receiver mayidentify a PLP for transmitting each component included in Service 0,Service 1 or Service N, and decode the PLP to acquire a desired service.

FIG. 82 illustrates a scheme of accessing video data and/or audio datain the ISO BMFF according to an embodiment of the present invention.

The figure illustrates a partial structure of the ISO BMFF. Theillustrated scheme of accessing video data and/or audio data includessynchronization between data during a local replay.

The receiver identifies a track using ‘tkhd’ in an ISO file.

The receiver may verify whether a media type is audio or video using‘hdlr’ (handler_type).

The receiver may initialize a decoder using sample description of‘stbl’, and decode data (samples) included in mdat using informationincluded therein.

An ‘stbl’ box may include an ‘stts’ box, a ‘ctts’ box, an ‘stsc’ box, an‘stco’ box and/or an ‘stsz’ box.

The stts' box indicates a decoding time. The ‘stts’ box includesinformation enabling indexing from a decoding time to a sample number.The stts' box may provide a pointer and a sample size derived from thesample number.

The ‘Ms’ box provides information about an offset between a decodingtime and a composition time.

The ‘stsc’ box includes attribute information related to a chunkincluding a sample, a location of the chunk and/or the sample. Samplesin media data may be grouped into chunks. Chunks may have differentsizes, and samples in one chunk may have different sizes.

The ‘stco’ box may include index information of each chunk included infiles. ‘stco’ box gives the offset of the start of a chunk into itscontaining media file.

‘stsz’ box contains the sample count and a table giving the size inbytes of each sample. This allows the media data itself to be unframed.The total number of samples in the media is always indicated in thesample count. ‘stsz’ box contains may contain information specifying thedefault sample size. If all the samples are the same size, theinformation contains that size value. If this information is set to 0,then the samples have different sizes, and those sizes are stored in thesample size table. If this information is not 0, it specifies theconstant sample size, and no array follows.

The receiver may synchronize a video sample (video data) with an audiosample (audio data) using the above-described information included inthe ‘stbl’ box.

FIG. 83 illustrates a scheme of accessing video data and/or audio datain the ISO BMFF according to another embodiment of the presentinvention.

The illustrated scheme of accessing video data and/or audio dataincludes synchronization between data during a streaming replay. In thiscase, the video data and/or the audio data are transmitted/received instates of being fragmented and/or segmented.’

The receiver acquires basic information necessary for file decoding froman initialization segment. The receiver identifies a track using ‘tkhd’in the ISO file.

The receiver may verify whether a media type is audio or video using‘hdlr’ (handler_type).

The receiver initializes a decoder using attribute information of mediaon a current track included in an ‘minf’ box.

The receiver identifies a media segment corresponding to the trackidentified by ‘tkhd’ using a ‘tfhd’ box in the media segment, andacquires a sample description index corresponding to sample descriptionof the ‘minf’ box.

The receiver extracts samples of the video data and/or the audio datausing base data offset information included in the ‘tfhd’ box, dataoffset information included in a ‘trun’ box and/or sample sizeinformation included in the ‘trun’ box.

The receiver performs synchronization between the samples of the videodata and/or the audio data using sample duration information and samplecomposition time offset information included in the ‘trun’ box.

A detailed transmission frame and transport packet transmittingbroadcast service will be described with reference to FIGS. 84 to 87.

FIG. 84 is a view illustrating a broadcast transmission frame accordingto an embodiment of the present invention.

According to the embodiment of FIG. 84, the broadcast transmission frameincludes a P1 part, an L1 part, a common PLP part, an interleaved PLPpart (e.g., a scheduled & interleaved PLP's part), and an auxiliary datapart.

According to the embodiment of FIG. 84, the broadcast transmissiondevice transmits information on transport signal detection through theP1 part of the transmission frame. Additionally, the broadcasttransmission device may transmit turning information on broadcast signaltuning through the P1 part.

According to the embodiment of FIG. 84, the broadcast transmissiondevice transmits a configuration of the broadcast transmission frameand, characteristics of each PLP through the L1 part. At this pint, thebroadcast reception device 100 decodes the L1 part on the basis of theP1 part to obtain the configuration of the broadcast transmission frameand the characteristics of each PLP.

According to the embodiment of FIG. 84, the broadcast transmissiondevice may transmit information commonly applied to PLPs through thecommon PLP part. According to a specific embodiment of the presentinvention, the broadcast transmission frame may not include the commonPLP part.

According to the embodiment of FIG. 84, the broadcast transmissiondevice transmits a plurality of components included in broadcast servicethrough an interleaved PLP part. At this point, the interleaved PLP partincludes a plurality of PLPs.

Moreover, according to the embodiment of FIG. 84, the broadcasttransmission device may signal to which PLP components configuring eachbroadcast service are transmitted through an L1 part or a common PLPpart. However, the broadcast reception device 100 decodes all of aplurality of PLPs of an interleaved PLP part in order to obtain specificbroadcast service information on broadcast service scan.

Unlike the embodiment of FIG. 84, the broadcast transmission device maytransmit a broadcast transmission frame including a broadcast servicetransmitted through a broadcast transmission frame and an additionalpart that includes information on a component included in the broadcastservice. At this point, the broadcast reception device 100 may instantlyobtain information on the broadcast service and the components thereinthrough the additional part. This will be described with reference toFIG. 85.

FIG. 85 is a view of a broadcast transmission frame according to anotherembodiment of the present invention.

According to the embodiment of FIG. 85, the broadcast transmission frameincludes a P1 part, an L1 part, a fast information channel (FIC) part,an interleaved PLP part (e.g., a scheduled & interleaved PLP's part),and an auxiliary data part.

Except the FIC part, other parts are identical to those of FIG. 84.

The broadcast transmission device transmits fast information through theFIC part. The fast information may include configuration information ofa broadcast stream transmitted through a transmission frame, simplebroadcast service information, and service signaling relating to acorresponding service/component. The broadcast reception device 100 mayscan broadcast service on the basis of the FIC part. In more detail, thebroadcast reception device 100 may extract information on broadcastservice from the FIC part.

FIG. 86 is a view illustrating a structure of a transport packettransmitting a broadcast service according to an embodiment of thepresent invention.

In the embodiment of FIG. 86, a transport packet transmitting abroadcast service includes a Network Protocol field, an Error Indicatorfield, a Stuffing Indicator field, a Pointer field, a Stuffing bytesfield, and payload data.

The Network Protocol field represents the type of a network protocol.According to a specific embodiment of the present invention, a value ofthe Network Protocol field may represent the IPv4 protocol or a framepacket type. In more detail, as shown in the embodiment of FIG. 87, whena value of the Network Protocol field is 000, it may represent the IPv4protocol. In more detail, as shown in the embodiment of FIG. 87, when avalue of the Network Protocol field is 111, it may represent aframe_packet_type protocol. At this point, framed_packet_type may be aprotocol defined by ATSC A/153. In more detail, framed_packet_type mayrepresent a network packet protocol not including a field representinginformation on the length. According to a specific embodiment of thepresent invention, the Network Protocol may be a 3-bit field.

The Error Indicator field represents that an error is detected from acorresponding transport packet. In more detail, if a value of the ErrorIndicator field is 0, it represents that no error is detected from acorresponding packet and if a value of the Error Indicator field is 1,it represents that an error is detected from a corresponding packetAccording to a specific embodiment of the present invention, the ErrorIndicator field may be a 1-bit field.

The Stuffing Indicator field represents whether stuffing bytes areincluded in a corresponding transport packet. At this point, thestuffing bytes represent data included in a payload to maintain thelength of a fixed packet. According to a specific embodiment of thepresent invention, when a value of the Stuffing Indicator field is 1, atransport packet includes a stuffing byte and when a value of theStuffing Indicator field is 0, a transport packet includes no stuffingbyte According to a specific embodiment of the present invention, theStuffing Indicator field may be a 1-bit field.

The Pointer field represents a start point of a new network packet in apayload part of a corresponding transport packet. According to aspecific embodiment of the present invention, when a value of thePointer field is 0x7FF, it may represent that there is no start point ofa new network packet. Additionally, According to a specific embodimentof the present invention, when a value of the Pointer field is not0x7FF, it may represent an offset value from the last part of atransport packet header to the start point of a new network packet.According to a specific embodiment of the present invention, the Pointerfield may be an 11-bit field.

The Stuffing Bytes field represents a stuffing byte filling between theheader and the payload data to maintain a fixed packet length.

A configuration of a broadcast reception device for receiving broadcastservice will be described below.

FIG. 88 is a view that a broadcast service signaling table and broadcastservice transmission path signaling information signal broadcast serviceand a broadcast service transmission path.

The broadcast service signaling table may signal broadcast serviceinformation. In more detail, the broadcast service signaling table maysignal a media component that broadcast service includes. Additionally,the broadcast service signaling table may signal broadcast service and atransmission path of a media component that the broadcast serviceincludes. For this, the broadcast service signaling table may includebroadcast service transmission path signaling information. In theembodiment of FIG. 88, the broadcast service signaling table includesinformation on a plurality of broadcast services. At this point, thebroadcast service signaling table includes media component signalinginformation signaling a plurality of media components respectivelyincluded in a plurality of broadcast services. Especially, the broadcastservice signaling table includes broadcast service transmission pathsignaling information signaling transmission paths of a plurality ofmedia components. For example, it is shown that the broadcast receptiondevice 100 may transmit Video 1 in Service 0 through PLP 0 according tothe signaling table. Additionally, it is shown that the broadcastreception device 100 may transmit Audio 1 in Service N through internetnetwork according to the signaling table. At this point, the PLP is aseries of logical data delivery paths identifiable on a physical layer.The PLP may be also referred to as a data pipe.

FIG. 89 is a view illustrating a broadcast service signaling tableaccording to an embodiment of the present invention.

The broadcast service signaling table may include at least one ofbroadcast service identification information, information representingthe current state of a broadcast service, the name of a broadcastservice, information representing whether a protection algorithm forbroadcast service is applied, category information of a broadcastservice, and media component signaling information signaling a mediacomponent that a broadcast service includes. The media componentsignaling information signaling a media component that the broadcastservice includes may include information representing whether each mediacomponent is essential to a corresponding broadcast service.Additionally, the media component signaling information signaling amedia component that the broadcast service includes may includeinformation relating to each component.

In more detail, as shown in the embodiment of FIG. 89, the broadcastservice signaling table may include at least one of a table_id field,section_syntax_indicator field, a private_indicator field, asection_length field, a table_id_extension field, a version_numberfield, a current_next_indicator field, a section_number field, alast_section_number field, a num_services field, a service_id field, aservice_status field, an SP_indicator field, a short_service_name_lengthfield, a short_service_name field, a channel_number field, aservice_category field, a num_components field, anessential_component_indicator field, a num_component_level_descriptorfield, a component_level_descriptor field, anum_service_level_descriptors field, and a service_level_descriptorfield.

The table_id field represents an identifier of a broadcast servicesignaling information table. At this point, a value of the table_idfield may be one of reserved id values defined in ATSC A/65. Accordingto a specific embodiment of the present invention, the table_id fieldmay be an 8-bit field.

The section_syntax_indicator field represents whether the broadcastservice signaling information table is a private section table in a longformat of MEPG-2 TS standard. According to a specific embodiment of thepresent invention, the section_syntax_indicator field may be a 1-bitfield.

The private_indicator field represents whether a current tablecorresponds to a private section. According to a specific embodiment ofthe present invention, the private_indicator field may be a 1-bit field.

The section_length field represents the length of a section after thesection_length field. According to a specific embodiment of the presentinvention, the section_length field may be a 12-bit field.

The table_id_extension field represents a value for identifying abroadcast service signaling information table in combination with thetable_id field. Especially, the table_id field may include aSMT_protocol_version field representing a protocol version of a servicesignaling information table. According to a specific embodiment of thepresent invention, the SMT_protocol_version field may be an 8-bit field.

The version_number field represents a version of a service signalingtable. The broadcast reception device 100 may determine the availabilityof a service signaling information table on the basis of a value of thevserion_number field. In more detail, when a value of the version_numberfield is identical to a version of a previously received servicesignaling table, the information of the service signaling table may notbe used. According to a specific embodiment of the present invention,the version_number field may be a 5-bit field.

The current_next_indicator field represents whether information of abroadcast service signaling table is currently available. In moredetail, when a value of the current_next_indicator field is 1, it mayrepresent that the information of the broadcast service signaling tableis available. Moreover, when a value of the current_next_indicator fieldis 1, it may represent that the information of the broadcast servicesignaling table is available next time. According to a specificembodiment of the present invention, the current_next_indicator fieldmay be a 1-bit field.

The section_number field represents a current section number. Accordingto a specific embodiment of the present invention, the section_numberfield may be an 8-bit field.

The last_section_number field represents the last section number. Whenthe size of a broadcast service signaling table is large, it may bedivided into a plurality of sections and then transmitted. At thispoint, the broadcast reception device 100 determines whether allsections necessary for a broadcast service signaling table are receivedon the basis of the section_number field and the last_section_numberfield. According to a specific embodiment of the present invention, thelast_section_number field may be an 8-bit field.

The service_id field represents a service identifier for identifying abroadcast service. According to a specific embodiment of the presentinvention, the service_id field may be a 16-bit field.

The service_status field represents the current state of a broadcastservice. In more detail, it may represent whether the broadcast serviceis available currently. According to a specific embodiment of thepresent invention, when a value of the service_status field is 1, it mayrepresent that the broadcast service is available currently. Accordingto a specific embodiment of the present invention, the broadcastreception device 100 may determine whether to display a correspondingbroadcast service in a broadcast service list and a broadcast serviceguide on the basis of a value of the service_status field. For example,when a corresponding broadcast service is unavailable, the broadcastreception device 100 may not display the corresponding broadcast servicein a broadcast service list and a broadcast service guide. According toanother specific embodiment of the present invention, the broadcastreception device 100 may limit an access to a corresponding broadcastservice on the basis of a value of the service_status field. Forexample, when a corresponding broadcast service is unavailable, thebroadcast reception device 100 may limit an access to a correspondingbroadcast service through a channel up/down key. According to a specificembodiment of the present invention, the service_status field may be a2-bit field.

The SP_indicator field may represent whether service protection isapplied to at least one component in a corresponding broadcast service.For example, when a value of SP_indicator is 1, it may represent thatservice protection is applied to at least one component in acorresponding broadcast service. According to a specific embodiment ofthe present invention, the SP_indicator field may be a 1-bit field.

The short_service_name_length field represents the size of theshort_service_name field.

The short_service_name field represents the name of a broadcast service.In more detail, the short_service_name field may be displayed bysummarizing the name of a broadcast service.

The channel_number field displays a virtual channel number of acorresponding broadcast service.

The service_category field represents a category of a broadcast service.In more detail, the service_category field may represent at least one ofTV service, radio service, broadcast service guide, RI service, andemergency alerting. For example, as shown in the embodiment of FIG. 89,in the case that a value of the service_category field is 0x01, itrepresents TV service. In the case that a value of the service_categoryfield is 0x02, it represents radio service. In the case that a value ofthe service_category field is 0x03, it represents RI service. In thecase that a value of the service_category field is 0x08, it representsservice guide. In the case that a value of the service_category field is0x09, it represents emergency alerting. According to a specificembodiment of the present invention, the service_category field may be a6-bit field.

The num_component field represents the number of media components that acorresponding broadcast service includes. According to a specificembodiment of the present invention, the num_component field may be a5-bit field.

The essential_component_indicator field represents whether acorresponding media component is an essential media component essentialto a corresponding broadcast service presentation. According to aspecific embodiment of the present invention, theessential_component_indicator field may be a 1-bit field.

The num_component_level_descriptor field represents the number ofcomponent_level_descrptor fields. According to a specific embodiment ofthe present invention, the num_component_level_descriptor field may be a4-bit field.

The component_level_descriptor field includes an additional property fora corresponding component.

The num_service_level_descriptors field represents the number ofservice_level_descriptor fields. According to a specific embodiment ofthe present invention, the num_service_level_descriptors field may be a4-bit field.

The service_level_descriptor field includes an additional property for acorresponding service.

The service signaling table may further include information on ensemble.When the same Forward Error Correction (FEC) is applied to at least oneservice and transmitted, the ensemble represents a collection of the atleast one service. FIG. 93 is a view of a broadcast service signalingtable according to another embodiment of the present invention.

In more detail, as shown in the embodiment of FIG. 93, the broadcastservice signaling table may further include anum_ensemble_level_descriptors field and an ensemble_level_descriptorfield.

The num_ensemble_level_descriptors field represents the number ofensemble_level_descriptor fields. According to a specific embodiment ofthe present invention, the num_ensemble_level_descriptors field may be a4-bit field.

The ensemble_level_descriptor field includes an additional property fora corresponding ensemble.

Additionally, the service signaling table may further include streamidentifier information for identifying a media component. This will bedescribed in more detail with reference to FIG. 92.

FIG. 92 is a view of a stream identifier descriptor according to anotherembodiment of the present invention.

The stream identifier information includes at least one of adescriptor_tag field, a descriptor_length field, and a component_tagfield.

The descriptor_tag field represents a descriptor including streamidentifier information. According to a specific embodiment of thepresent invention, the descriptor_tag field may be an 8-bit field.

The descriptor_length field represents the length of stream identifierinformation after a corresponding field. According to a specificembodiment of the present invention, the descriptor_length field may bean 8-bit field.

The component_tag field represents a media component identifier foridentifying a media component. At this point, the media componentidentifier may have a different unique value than a media componentidentifier of another media component on a corresponding signalinginformation table. According to a specific embodiment of the presentinvention, the component_tag field may be an 8-bit field.

An operation for transmitting/receiving a broadcast service signalingtable will be described with reference to FIGS. 93 and 99.

The above broadcast service table is described as in a bitstream formatbut according to a specific embodiment of the present invention, abroadcast service table may be in an XML format.

FIG. 93 is a view illustrating an operation when a broadcasttransmission device transmits a broadcast service signaling tableaccording to an embodiment of the present invention.

The broadcast transmission device may include a transmission unit fortransmitting a broadcast signals and a control unit for controllingoperations of the broadcast transmission unit. A transmission unit mayinclude one or more processors, one or more circuits, and one or morehardware modules, which perform each of a plurality of functions thatthe transmission unit performs. In more detail, the transmission unitmay be a System On Chip (SOC) in which several semiconductor parts areintegrated into one. At this point, the SOC may be semiconductor inwhich various multimedia components such as graphics, audio, video, andmodem and a semiconductor such as a processor and D-RAM are integratedinto one. The control unit may include one or more processors, one ormore circuits, and one or more hardware modules, which perform each of aplurality of functions that the control unit performs. In more detail,the control unit may be a System On Chip (SOC) in which severalsemiconductor parts are integrated into one. At this point, the SOC maybe semiconductor in which various multimedia components such asgraphics, audio, video, and modem and a semiconductor such as aprocessor and D-RAM are integrated into one.

The broadcast transmission device obtains data to be contained in atransport packet and transmitted through the control unit in operationS101. The data that the broadcast transmission device transmits may bereal-time content or metadata relating to real-time content. In moredetail, real-time content may be a broadcast A/V content transmittedthrough a terrestrial broadcast network or enhancement data relating tobroadcast AV content.

The broadcast transmission device determines whether data obtainedthrough the control unit exceeds the size that a transport packet fordata transmission contains in operation 5103. In more detail, atransport packet that the broadcast transmission device is to use may bebased on a protocol using a fixed packet length. At this point, whendata to be transmitted exceeds the size that a packet covers, it isdifficult to transmit data smoothly. Additionally, when data to betransmitted is very smaller than a packet, it is inefficient to transmitonly a small size of one data in one packet. Accordingly, in order toovercome the inefficiency, the broadcast transmission device comparesthe sizes of a transport packet and data through the control unit.

If it is determined that a transport packet cannot contain the size ofdata that the broadcast transmission device is to transmit, thebroadcast transmission device segments data to be transmitted throughthe control unit in operation S107. The segmented data may be divided ina plurality of transport packets and then transmitted. Then, theplurality of transport packets may additionally include information foridentifying the segmented data. According to another embodiment, theinformation for identifying segmented data may be transmitted throughadditional datagram instead of a transport packet.

The broadcast transmission device packetizes data having a smaller sizethan segmented data or a transport packet through the control unit inoperation S109. In more detail, the broadcast transmission deviceprocesses data to be in a delivery from. The processed broadcast packetmay include a packet header and packet payload. Additionally, the packetpayload may include data and the header of a payload. Herein, besidesthe packet header, the payload header is a field for signaling payloaddata in the packet payload. Additionally, the packet payload includingsegmented data may include a segmented data header in addition to theheader of a payload. Herein, besides the payload header, the segmenteddata header is a field for signaling payload data in the packet payload.

According to an embodiment, the broadcast transmission device maypacketize one data in one packet. According to another embodiment, thebroadcast transmission device may packetize a plurality of data in onepacket. According to another embodiment, the broadcast transmissiondevice may segment and packetize one data in a plurality of packets.

As mentioned above, according to the size of data or the length of apacket, a packetized transport packet may vary. Therefore, it isnecessary for the broadcast transmission device to transmit differenttransport packets in distinguishable forms. According to an embodiment,the broadcast transmission device may packetize data by includinginformation representing the form of a packet in the payload header of atransport packet through the control unit. According to anotherembodiment, when it is difficult to distinguish data to be transmittedonly with information in the payload header, the control unit of thebroadcast transmission device may packetize data by additionallyincluding information for identifying the type of a transport packet.

The broadcast transmission device transmits the packetized broadcastpacket through the transmission unit in operation S1111. According to anembodiment, a broadcast packet may be transmitted through a terrestrialbroadcast network. According to another embodiment, a broadcast packetmay be transmitted through an internet network.

FIG. 94 is a view illustrating an operation when a broadcast receptiondevice receives a packetized broadcast packet according to an embodimentof the present invention.

The broadcast reception device 100 receives a packetized transportpacket through the broadcast reception unit 110 in operation S201.

The broadcast reception device 100 extracts a payload header from thereceived transport packet through the control unit 150 in operationS203. The control unit 150 may obtain payload data including data and apayload header signaling the payload data from the payload of thetransport packet. In more detail, the control unit 150 of the broadcastreception device 100 may extract additional information for providing atleast one of a broadcast content in the packet payload and anenhancement content relating to the broadcast content, from the receivedtransport packet.

According to an embodiment, the control unit 150 of the broadcastreception device 100 may extract at least one of payload errordetermination information, payload priority information, and payloadtype information from the payload header. In more detail, the payloaderror determination information represents whether there is an error inthe payload in a broadcast packet or whether a corresponding payloadincludes a content violating a predetermined syntax.

Additionally, the priority information represents a priority of data inthe payload. Additionally, the priority information represents propertyinformation of data in the payload. For example, in the case of apayload including signaling information of file format media data, thepriority information of a corresponding packet is set to the highestpriority.

Additionally, the payload type information represents the type of apacket payload including payload data. For example, the payload typeinformation may represent whether the broadcast transmission devicepacketizes one data in one packet payload or divides and packetizes onedata in a plurality of packet payloads.

The broadcast reception device 100 determines whether data in thepayload is media data from information in the extracted payload headerthrough the control unit 150 in operation S205. In more detail, thecontrol unit 150 of the broadcast reception device 100 may determine thetype of a payload in a corresponding packet on the basis of the packetheader information. According to an embodiment, the type of a payloadmay be media data including broadcast content and an enhancement contentrelating to the broadcast content. According to another embodiment, thetype of a payload may be metadata including additional informationnecessary for providing media data.

When it is determined that data in the payload is media data, thecontrol unit 150 of the broadcast reception device 100 determineswhether entire media data is included in one transport packet inoperation S207. According to a specific embodiment, according to thelength of a transport packet and the size of entire media data, thebroadcast transmission device may packetize the entire media data in onetransport packet. According to another embodiment, the broadcasttransmission device may divide entire media data and packetize them indifferent transport packets. Accordingly, the control unit 150 of thebroadcast reception device 100 may determine the type of a broadcastpacket through the payload header so as to extract complete media datafor content output.

On the other hand, according to an embodiment of the present invention,when the control unit 150 of the broadcast reception device 100determines that data in the payload is not media data, this will bedescribed in more detail with reference to FIG. 117.

When it is determined that entire media data is included in onetransport packet, the control unit 150 extracts media data from onepacket payload in operation 5209. According to an embodiment, thecontrol unit 150 of the broadcast reception device 100 may extract onlyone media data from one transport packet. According to anotherembodiment, the control unit 150 of the broadcast reception device 100may extract a plurality of media data from one transport packet. On theother hand, when it is determined that entire media data is not includedin a transport packet, the control unit 150 extracts media data from aplurality of packet payloads on the basis of a payload header and asegment data header in operation S211. In more detail, the control unit150 may obtain information of divided and packetized media data from thepayload header and the segment data header. Accordingly, the controlunit 150 may identify divided media data according to the obtainedinformation. That is, the control unit 150 may obtain the order ofdivided media data according to the obtained information. The controlunit 150 may concatenate media data obtained from different transportpackets on the basis of a corresponding order.

The broadcast reception device 100 provides content through the controlunit 150 in operation 5213. According to an embodiment, the control unit150 may provide content on the basis of extracted media data. Accordingto another embodiment, the control unit 150 may provide content on thebasis of concatenated media data.

The control unit 150 may output A/V content. According to anotherembodiment, the broadcast reception device 110 may output enhancementdata relating to A/V content.

FIG. 95 is a view illustrating a segment configuration according to anembodiment of the present invention.

On a packet based data transfer protocol, each packet is configured witha packet header and a packet payload as shown in FIG. 91 in general. Thepacket header may include information of a packet payload in a packet.The packet payload may include media data to be transmitted via abroadcast network or an internet network. Media data that the packetpayload includes may be at least one of audio, video, enhancementservice, and additional information.

FIG. 96 is a view illustrating a structure of a real-time transportprotocol (RTP) packet for real-time content transmission according to anembodiment of the present invention.

An RTP packet may include an RTP Header and an RTP Payload. The RTPheader include at least one of a Timestamp, a Synchronization sourceidentifier, and a Contributing source identifier.

The RTP Header may include at least one of a V (version) field, a P(padding) field, an X (extension) field, a CC field, an M (Marker bit)field, a Payload Type field, a Sequence Number field, and a Timestampfield.

The V (version) field represents version information of a correspondingRTP. According to a specific embodiment of the present invention, the V(version) field may be a 2-bit field.

The P (padding) field represents whether there are padding bits in apayload. According to a specific embodiment of the present invention,the P (padding) field may be a 1-bit field.

The X (extension) field represents whether there is an extension fieldin the RTP Header. According to a specific embodiment of the presentinvention, the X (extension) field may be a 1-bit field.

The CC field represents the number of Contributing sources. According toa specific embodiment of the present invention, the CC field may be a4-bit field.

The M (Marker bit) field may represent a different meaning according tothe Payload type. For example, when a transport object is a file, the M(Marker bit) field may represent the end of the file. According toanother embodiment, when a transport object is video or audio data, theM (Marker bit) field may represent the first or last object of relatedaccess units. According to a specific embodiment of the presentinvention, the M (Marker bit) field may be a 1-bit field.

The Payload Type field represents the type of an RTP Payload. Accordingto a specific embodiment of the present invention, the Payload Typefield may be a 7-bit field.

The Sequence Number field represents the sequence number of an RTPpacket. According to a specific embodiment of the present invention, theSequence Number field may be a 16-bit field.

The Timestamp field may represent time information relating to an RTPpacket. The Timestamp field may be interpreted differently according toa value of the Payload Type field. According to a specific embodiment ofthe present invention, the Timestamp field may be a 32-bit field.

RTP payload may be included in an audio/video access unit according tothe payload type of RTP Header. For example, in the case of H.264, anetwork abstract layer (NAL) unit may be included.

FIG. 97 is a view illustrating a media file format based on an ISO basemedia file format (ISO BMFF) according to an embodiment of the presentinvention.

As shown in FIG. 97, the media file format may include one ftyp and atleast one moov, moof, and mdat in general.

ftyp represents the type and suitability of a media file. Ftyp islocated at the front in a media file if possible.

moov is a container for all media data. In more detail, moov is acontainer box for single track of presentation. Presentation may beconfigured with one or more tracks. Each track is separated from anothertrack in presentation. According to an embodiment, a track may containmedia data and according to another embodiment, a track may containinformation for packetized streaming protocol.

mdat is a container of media data and moof contains information on mdat.

FIG. 98 is a view illustrating a configuration of a payload header in apacket payload according to an embodiment of the present invention.

Currently, a real-time transport protocol is mostly transmitted based onan access unit of a media file. In more detail, an access unit refers toa minimum unit for transmitting a media file or data. Accordingly, thereis insufficient consideration on a method of transmitting media fileformat based data in real-time.

According to an embodiment of the present invention, a broadcasttransmission device may transmit one file format based media datathrough a payload included in one transport packet. In this case, thetransport packet may be referred to as a single unit packet. Accordingto an embodiment of the present invention, a broadcast transmissiondevice may transmit a plurality of file format based media data througha payload included in one transport packet. In this case, the transportpacket may be referred to as an aggregation packet. According to anotherembodiment of the present invention, a broadcast transmission device maydivide one file format based media data into several transport packetsand may then transmit them. In this case, the transport packet may bereferred to as a fragmented packet. According to another embodiment ofthe present invention, a broadcast transmission device may transmit oneor a plurality of metadata for media stream through the payload of onetransport packet. According to another embodiment, the broadcasttransmission device may transmit one metadata through the payloads of aplurality of transport packets.

Additionally, a broadcast transmission device according to an embodimentof the present invention may transmit media data through variousprotocols. The protocol may include at least one of a real-timetransport protocol (RTP), an asynchronous layered coding (ALC), and alayered coding transport (LCT).

In more detail, a broadcast transmission device may insert a fieldrepresenting information on a payload type in the header of a transportpacket to represent that there is file format based media data in apayload through a corresponding field. For example, in the case of theRTP, the payload type field of a header may represent the data type of apayload and a specific value may be assigned to a corresponding field asa payload type value for file format based media data. Then, in thiscase, when data including the end of one media file is included in thepayload of a packet, the M field of an RTP packet header may be set to1.

In order to overcome the above issues, a payload header according to anembodiment of the present invention may include at least one ofinformation representing whether there is an error or syntax error ondata in a payload, information representing the priority of data, andinformation representing the type of data. In this case, informationrepresenting whether there is an error or syntax error on data in thepayload of a payload header may be referred to as an F field. Accordingto an embodiment, the information representing whether there is an erroror syntax error on data in the payload of a payload header may be set to1 as forbidden_zero_bit when there is an error or syntax violation ondata in a payload. In more detail, the information representing whetherthere is an error or syntax error on data in the payload of a payloadheader may be one bit.

Additionally, information representing the priority of data in a payloadheader may be referred to as an information Priority field. According toan embodiment, the information representing the priority of data is afield representing the priority of payload data. Then, the informationrepresenting the priority of data may represent whether payload dataincludes important metadata on a media file format.

For example, in ISO BMFF, in the case of payload data including ftyp andmoov, information representing the priority of data may be set to thehighest priority. According to an embodiment, information representingthe priority of data may represent the highest priority highest(highest), a relatively lower priority than the highest priority(medium), and the lowest priority (low) through a control unit of abroadcast transmission device. In this case, information representingthe priority of data may be set to 0x00 in the case of the highestpriority, 0x01 in the case of a relatively lower priority than thehighest priority, and 0x02 in the case of the lowest priority. The abovesetting value is just one exemplary and may be wet to another arbitraryvalue.

Additionally, in this case, information representing the type of datamay be referred to as a type field. In more detail, through informationrepresenting the type of data, the control unit 150 of the broadcastreception device 100 may identify whether a transport packet is a packettransmitting one data by one packet, a packet transmitting a pluralityof different data by one packet, or a packet transmitting data obtainedby dividing one into a plurality of data.

Additionally, through information representing the type of data, thecontrol unit 150 of the broadcast reception device 100 may identifywhether a transport packet is a packet transmitting metadata includingtime information of content or a packet transmitting metadata includingdescription information of content.

According to an embodiment, in the case of a packet transmitting onedata by one packet, the broadcast reception device may set informationrepresenting the type of data to 0x00. Additionally, in the case of apacket transmitting a plurality of different data by one packet, thebroadcast reception device may set information representing the type ofdata to 0x01. Additionally, in the case of a packet dividing one dataand transmitting divided data, the broadcast reception device may setinformation representing the type of data to 0x02.

Additionally, the broadcast transmission device may packetize metadataincluding presentation or decoding time information of content insteadof media data and may then transmit the packetized metadata. In the casethe broadcast reception device may set information representing the typeof data to 0x03. Moreover, the time information may be referred to astimeline data.

Additionally, the broadcast transmission device may packetize andtransmit metadata including description information of content. In thecase the broadcast reception device may set information representing thetype of data to 0x04. Moreover, the time information may be referred toas labeling data.

However, the above setting values are just exemplary so that the presentinvention is not limited to the above values. According to a specificembodiment of the present invention, the type field may be a 5-bitfield.

FIGS. 99 and 100 are views illustrating a payload configuration of atransport packet in which one media data is packetized in one packet.

As shown in FIG. 99, a packet in which one media data is included in onepacket may be referred to as a single unit packet. The payload of asingle unit packet may include a payload header and payload data. Thepayload data may include fragmented data including one file format basedmedia data. According to an embodiment, when a transport protocol uses atransport packet of a fixed length, payload data may include paddingbits in addition to fragmented data. Herein the padding bit refers to abit for filling the remaining space after filling data in a transportpacket.

FIG. 100 is a detailed view of a transport packet shown in FIG. 99. Asshown in FIG. 100, a payload header may include at least one ofinformation representing whether there is an error or syntax error indata in a payload, information representing the priority of data, andinformation representing the type of data.

As shown in FIG. 100, information representing whether there is an erroror syntax error on data in a payload may include a value representing acontent that there is no error and syntax violation. According to aspecific embodiment of the present invention, a corresponding value maybe 0.

Since a media file in payload data includes important data such as ftyp,Information representing the priority of data may have the highestpriority. As mentioned above, in the case of ftyp; since ftyp includesinformation for signaling a media file, it may have the highestpriority. According to a specific embodiment of the present invention, avalue representing the highest priority may be 0x00.

Since one media file is all included in one packet payload, Informationrepresenting the type of data may represent a single unit packet.According to a specific embodiment, information representing the type ofdata may have a value of 0x00. Additionally, a padding bit may beselectively inserted into payload data according to the length andtransport protocol of media file.

FIGS. 101 and 102 are views illustrating a configuration of a transportpacket in which a plurality of media data are packetized in one packet.The above packet may be referred to as an aggregation packet. As shownin FIG. 101, when the payload of one transport packet includes aplurality of different file format based media data, payload data mayinclude a plurality of aggregation units. Each aggregation unit mayinclude another file format based media data. According to anembodiment, when a transport protocol uses a packet of a fixed length,payload data may include padding bits in addition to fragmented data.

According to an embodiment, one aggregation unit may include at leastone of information representing the length of an aggregation unit andaggregation data. In this case, information representing the length ofan aggregation unit may be referred to as an aggregation unit lengthfield. According to a specific embodiment of the present invention, theaggregation unit may be 16 bits. Additionally, aggregation unit datarepresent data in one file.

FIG. 102 is a view illustrating a configuration of an aggregation unitaccording to another embodiment of the present invention. Oneaggregation unit may further include information representing the typeof a file in an aggregation unit in addition to the embodiment of FIG.101.

Information representing the type of aggregation may be referred to asan aggregation unit type field. According to a specific embodiment, thebroadcast transmission device may set the aggregation type to 0x00.

According to another embodiment, the aggregation type may represent thata corresponding aggregation unit includes a file in Self-initializingSegment format on MPEG-Dynamic Adaptive Streaming over HTTP (DASH).Herein, a self-initializing segment is obtained by integrating aninitializing segment and a media segment without an additionalinitializing segment. In more detail, the self-initializing segment mayinclude a media segment and its media form. According to a specificembodiment, in this case, the broadcast transmission device may set theaggregation type to 0x01.

According to another embodiment, the aggregation type may represent thata corresponding aggregation unit includes a file in InitializationSegment format on MPEG-DASH. Herein, the initializing segment is aformat following ISO BMFF. In more detail, the initializing segmentneeds to include ftyp and moov. But, it does not include moof. Accordingto a specific embodiment, in this case, the broadcast transmissiondevice may set the aggregation type to 0x02.

FIGS. 103 and 109 are views illustrating a payload configuration of atransport packet (hereinafter referred to as a fragmented packet) inwhich one media data is divided and packetized into a plurality oftransport packets. FIG. 103 is a view illustrating the payload of afragmented packet according to an embodiment of the present invention.As shown in FIG. 103, the payload of a fragmented packet may include afragmentation unit. Additionally, when a transport protocol uses apacket of a fixed length, the payload of a fragmented packet may includepadding bits.

According to an embodiment, a fragmentation unit FU may include at leastone a Fragmentation unit header and Fragmentation unit data. TheFragmentation unit data may include part of one file format based mediadata. The Fragmentation unit header may include information offragmentation unit data.

In more detail, the fragmentation unit header may include at least oneof information representing whether fragmentation unit data includes thestart part data among entire file media data, information representingwhether fragmentation unit data includes the end part data among entirefile media data, and information representing the type of afragmentation unit.

According to an embodiment, the information representing whetherfragmentation unit data includes the start part data among entire filemedia data may be referred to as a start bit field. In more detail, thestart part data may be part of entire data including the first bit ofentire media data.

For example, the fragmentation unit data of a corresponding payloadincludes start part data, the broadcast transmission device may setinformation representing whether fragmentation unit data includes thestart part data among entire file media data to 1. In more detail, theinformation representing whether fragmentation unit data includes thestart part data among entire file media data may be one bit.

According to an embodiment, the information representing whetherfragmentation unit data includes the end part data among entire filemedia data may be referred to as an end bit field. In more detail, theend part data may be part of entire data including the end bit of entiremedia data.

For example, the fragmentation unit data of a corresponding payloadincludes end part data, the broadcast transmission device may setinformation representing whether fragmentation unit data includes theend part data among entire file media data to 1. In more detail, theinformation representing whether fragmentation unit data includes theend part data among entire file media data may be one bit.

According to an embodiment, information representing the type of afragmentation unit may be referred to as a fragmentation unit typefield.

According to an embodiment, a fragmentation unit type may represent thata corresponding packet indicates that a fragmentation unit includes afile format based basic file. In more detail, the file format basedbasic file may be a media file having a file format based on ISO BMFF.According to a specific embodiment, the broadcast transmission devicemay set the fragmentation unit type to 0x00.

According to another embodiment, the fragmentation unit type mayrepresent that a corresponding fragmentation unit includes a file inSelf-initializing Segment format on MPEG-DASH. According to a specificembodiment, in this case, the broadcast transmission device may set thefragmentation unit type to 0x01.

According to another embodiment, the fragmentation unit type mayrepresent that a corresponding fragmentation unit includes a file inInitialization Segment format on MPEG-DASH. According to a specificembodiment, in this case, the broadcast transmission device may set thefragmentation unit to 0x02.

According to another embodiment, the fragmentation unit type mayrepresent that a corresponding fragmentation unit includes a file inmedia Segment format on MPEG-DASH. According to a specific embodiment,in this case, the broadcast transmission device may set thefragmentation unit to 0x03.

In more detail, information representing a fragmentation unit type maybe six bits.

FIG. 104 is a view illustrating a configuration of a payload in afragmented packet according to another embodiment of the presentinvention. The embodiment of FIG. 104 may be applied to the case thereis no information relating to the order of a transport packet in theheader therein.

As shown in FIG. 104, the fragmentation unit header in a fragmentationunit FU may include at least one of information representing whetherfragmentation unit data includes the start part data among entire filemedia data, information representing whether fragmentation unit dataincludes the end part data among entire file media data, informationrepresenting the type of a fragmentation unit, and informationrepresenting the order in entire data of a fragmentation unit. Among theinformation, the remaining information other than the informationrepresenting the order of a fragmentation unit is identical to thatdescribed with reference to FIG. 103.

The information representing the order of a fragmentation unit may bereferred to as a fragmentation number field. In more detail, when fileformat based media data is divided into a plurality of fragmentedpackets, the broadcast transmission device may set a value to theinformation representing the order of a fragmentation unit to assign theorder of a corresponding packet. According to a specific embodiment ofthe present invention, the Fragmentation number field may be an 8-bitfield.

FIG. 105 is a view when a broadcast transmission device fragments an ISOBMFF based media file into a plurality of packets. As shown in FIG. 105,in ISO BMFF based media file may include ftyp and moov, and a pluralityof moof and mdat.

The broadcast transmission device may divide an ISO BMFF based mediafile into a plurality of files and may then include them in differentfragmentation unit data. Additionally, the broadcast transmission devicemay include related information in a payload header by dividing an ISOBMFF based media file.

FIG. 106 is a view illustrating first fragmentation unit data packetizedby the broadcast transmission device of FIG. 105.

As shown in FIG. 106, according to an embodiment of the presentinvention, the broadcast transmission device determines that there is noerror or syntax error in a corresponding packet and sets the F field to0.

Additionally, the broadcast transmission device may set the Priorityfield to a value representing the highest priority. According to aspecific embodiment of the present invention, a corresponding value maybe 0x00.

Additionally, the broadcast transmission device may set the Type fieldto a value representing a packet for dividing one file format basedmedia file into several payloads and transmitting them. According to aspecific embodiment of the present invention, a corresponding value maybe 0x02.

The payload data may include a fragmentation unit. Again, thefragmentation unit may include a Start bit field, an End bit field, afragmentation unit type field, and a fragmentation unit data field.

The broadcast transmission device may set the Start bit field to a valuerepresenting a content that a corresponding packet includes the startdata of a media file. In more detail, since a first fragmentation unitincludes the start data of media data as shown in FIG. 105, thebroadcast transmission device may set a value representing acorresponding content to the start bit field.

Moreover, the broadcast transmission device may set the End bit field ofa first fragmentation unit shown in FIG. 106 to a value representing acontent that the end data of a media file is not included. According toa specific embodiment, the broadcast transmission device may set the Endbit field to 0 to represent a content that a corresponding packet doesnot include the end data of a media file.

Moreover, as shown in FIG. 106, the broadcast transmission device mayset the fragmentation unit type field to a value representing a contentthat the first fragmentation unit includes a file format based basicform of file. In more detail, the file format based basic form may befile format data following ISO BMFF. According to a specific embodiment,the broadcast transmission device may set the fragmentation unit typefield to 0x00 to represent corresponding content.

FIGS. 107 to 109 are views illustrating a fragmentation unit includingremaining data except for the start data in the fragmentation unit dataof FIG. 105 according to an embodiment of the present invention.

As shown in FIG. 107, according to an embodiment of the presentinvention, the broadcast transmission device may set the F field of apayload header to a value representing that there is no error or syntaxerror in a corresponding packet. According to a specific embodiment, thebroadcast transmission device may set the F field to 0. Additionally,the broadcast transmission device sets the Priority field to a valuerepresenting the payload data shown in FIG. 107 has a relatively lowpriority.

According to a specific embodiment, data signaling entire media data maynot be included from a second fragment unit. Accordingly, since thesecond fragmentation unit has a relatively lower priority than the firstfragmentation unit, the priority field may be set to a value having arelatively lower priority. For example, a corresponding value may be0x01.

Additionally, the broadcast transmission device may set the Type fieldto 0x02 as a Fragmented packet that a corresponding packet represents apacket dividing one file format based media file into several payloadsand transmitting them. FIG. 108 is a view illustrating a payloadconfiguration when payload data does not include fragmentation unit dataincluding start data and fragmentation unit data including end data.

According to an embodiment of the present invention, since thefragmentation unit data of FIG. 108 does not include start data and enddata, the broadcast transmission device may set the start bit field andthe end bit field to a value representing corresponding information.According to a specific embodiment, the broadcast transmission devicemay set the start bit and end bit fields to 0.

Additionally, the broadcast transmission device may set the content thata fragmentation unit type field includes a file format based basic formof file to a specific value of a fragmentation unit type field. In moredetail, the file format based basic form may be file format datafollowing ISO BMFF. According to a specific embodiment, the broadcasttransmission device may set the fragmentation unit type field to 0x00 torepresent corresponding content. File format based media data dividedinto packets may have a unique order from an entire file. The broadcastreception device 100 may identify that the fragmentation unit datadivided through the control unit 150 includes the start part amongentire data on the basis of the start bit field. Additionally, the factthat the fragmentation unit data includes the end part in entire datamay be identified on the basis of the End bit field. However, there maybe a case that cannot be identified only by the Start bit field and theEnd bit field.

When the fragmentation unit data does not include start data or end datain entire data, the broadcast reception device 100 may identify acorresponding packet through information representing the order of thefragmentation unit data included in a payload according to anembodiment. In more detail, information representing the order offragmentation unit data may be a fragmentation number field.Additionally, a broadcast transmission device may set the order ofcorresponding fragmentation unit data to the above-mentionedpresentation field.

However, according to another embodiment, a transport packet may notinclude order information of fragmentation unit data. In this case,according to an embodiment, a broadcast transmission device may insertinformation for identifying the order of fragmentation unit data into apacket header. The information for identifying the order offragmentation unit data into a packet header may be referred to as asequence number field. According to another embodiment, a broadcasttransmission device may insert information for identifying the order offragmentation unit data into offset information of an IP datagram.

FIG. 109 is a view illustrating a configuration of a payload including afragmentation unit including the end data among divided entire mediadata. In more detail, FIG. 109 is a view illustrating a payloadconfiguration when payload data does not include fragmentation unit dataincluding start data but includes fragmentation unit data including enddata.

According to an embodiment of the present invention, since thefragmentation unit data of FIG. 109 includes end data, the broadcasttransmission device may set the start bit field and the end bit field toa value representing corresponding information. According to a specificembodiment, the broadcast transmission device may set the start field to0. Then, the broadcast transmission device may set the end bit field to1.

Additionally, a broadcast transmission device may set the fragmentationunit type field to represent the content that media data including acorresponding packet includes a basic form of file starting from ISOBMFF based ftyp. According to a specific embodiment, a broadcasttransmission device may set the fragmentation unit type field to 0x00.

Data that a broadcast transmission device transmits through a transportpacket may include metadata in addition to the above-mentioned mediadata. The metadata represents additional information necessary forproviding media data. Hereinafter, referring to FIGS. 110 to 117,suggested are a broadcast transmission device and an operating methodthereof, and a broadcast reception device and an operating methodthereof, in order for packetizing metadata in a transport packet andtransmitting and receiving it.

Additionally, hereinafter, timeline information is mainly described asone example of metadata. The timeline information is a series of timeinformation for media content. In more detail, the timeline informationmay be a series of time information for presentation or decoding.

Additionally, the timeline information may include base timelineinformation. The basic timeline means a reference timeline necessary forsynchronizing media data transmitted through a plurality of differenttransmission networks. In more detail, when the timeline of media datatransmitted through a second transmission network is mapped into thetimeline of media data transmitted through a first transmission network,the timeline of the media data transmitted through the firsttransmission network becomes a basic timeline.

Moreover, the broadcast transmission device may express the metadata inXML format. Additionally, the broadcast transmission device may expressthe metadata in a descriptor format includable in a signaling table.

FIG. 110 is a view illustrating a timeline signaling table of metadataaccording to an embodiment of the present invention.

According to an embodiment of the present invention, the timelinesignaling table may include information representing metadata relatingto a timeline or information that corresponding metadata includes atimeline component access unit. The above information may be referred toas an identifier field. According to a specific embodiment of thepresent invention, the identifier field may be an 8-bit field.

Additionally, according to an embodiment of the present invention, thetimeline signaling table may include information representing the lengthof timeline information of a timeline component access unit. The aboveinformation may be referred to as an AU_length field. According to aspecific embodiment of the present invention, the AU_length field may bea 32-bit field.

Additionally, according to an embodiment of the present invention, thetimeline signaling table may include information on whether includinglocation information on services and content components relating to atimeline component access unit. The above information may be referred toas a location_flag field. According to a specific embodiment of thepresent invention, the location_flag field may be a 1-bit field.

Additionally, according to an embodiment of the present invention, thetimeline signaling table may include version information of a timestampin a timeline component access unit. The timestamp represents timeinformation through which a corresponding access unit needs to beoutputted in a continuous timeline. The above information may bereferred to as a timestamp_version field. According to a specificembodiment of the present invention, the timestamp_version field may bea 1-bit field.

Additionally, according to an embodiment of the present invention, thetimeline signaling table may include timestamp type information of atimeline component access unit. The above information may be referred toas a timestamp_type field.

According to an embodiment, the timestamp type information may be set toa value representing a decoding time of a service or content componentrelating to a timeline component access unit. In more detail, thedecoding time of a content component may be referred to as a decodingtimestamp. According to a specific embodiment, the broadcasttransmission device may set timestamp type information to 0x00 whencorresponding information represents a decoding time.

According to another embodiment, the timestamp type information may beset to a value representing the presentation time of a service orcontent component relating to a timeline component access unit. In moredetail, the presentation time of a content component may be referred toas a presentation timestamp. According to a specific embodiment, thebroadcast transmission device may set timestamp type information to 0x01when corresponding information represents a presentation time.

Moreover, according to a specific embodiment of the present invention,the timestamp_type field may be a 1-bit field.

Additionally, according to an embodiment of the present invention, thetimeline signaling table may include timestamp format information of atimeline component access unit. The above information may be referred toas a timestamp_format field.

According to an embodiment, the timestamp format information mayrepresent that a timestamp in a timeline component access unit is aformat of a media time. According to a specific embodiment, thebroadcast transmission device may set the timestamp_format field to 0x00to represent that the timestamp format of a corresponding access unit isa media time format.

According to another embodiment, the timestamp format information mayrepresent that a timestamp in a timeline component access unit is aformat of a Network time protocol (NTP). According to a specificembodiment, the broadcast transmission device may set thetimestamp_format field to 0x01 to represent that the timestamp format ofa corresponding access unit is an NTP format.

According to another embodiment, the timestamp format information mayrepresent that a timestamp in a timeline component access unit is aformat of a precision time protocol (PTP). According to a specificembodiment, the broadcast transmission device may set thetimestamp_format field to 0x02 to represent that the timestamp format ofa corresponding access unit is a PTP format.

According to another embodiment, the timestamp format information mayrepresent that a timestamp in a timeline component access unit is aformat of a timecode. According to a specific embodiment, the broadcasttransmission device may set the timestamp_format field to 0x03 torepresent that the timestamp format of a corresponding access unit is atimecode format. Moreover, according to a specific embodiment of thepresent invention, the timestamp_format field may be a 4-bit field.

Additionally, according to an embodiment of the present invention, thetimeline signaling table may include location information on a componentof service or content relating to information in a timestamp in atimeline component access unit. The above information may be referred toas a location field.

Additionally, according to an embodiment of the present invention, thetimeline signaling table may include information representing the lengthof the location information. The information representing a locationinformation length may be referred to as a location_length field.According to a specific embodiment of the present invention, thelocation_length field may be an 8-bit field.

Additionally, according to an embodiment of the present invention, thetimeline signaling table may include timestamp format versioninformation of a basic timestamp that is a matching reference. The aboveinformation may be referred to as an origin_timestamp_version field.

According to an embodiment, when the origin_timestamp_version field isset to 0, this represents that a timestamp format has a 32-bit format.According to another embodiment, when the origin_timestamp_version fieldis set to 1, this represents that a timestamp format has a 64-bitformat.

Additionally, according to an embodiment of the present invention, thetimeline signaling table may include timestamp type information of abasic timeline. The above information may be referred to as anorigine_timestamp_type field.

According to an embodiment, the origine_timestamp_type field may be setto a value representing a decoding time of a service or contentcomponent relating to a basic timeline. In more detail, the decodingtime of a content component may be referred to as a decoding timestamp.According to a specific embodiment, the broadcast transmission devicemay set the origine_timestamp_type field to 0x00 when correspondinginformation represents a decoding time.

According to another embodiment, the origine_timestamp_type field may beset to a value representing a presentation time of a service or contentcomponent relating to a basic timeline. In more detail, the presentationtime of a content component may be referred to as a presentationtimestamp. According to a specific embodiment, the broadcasttransmission device may set the origine_timestamp_type field to 0x01when corresponding information represents a presentation time.

Additionally, according to an embodiment of the present invention, thetimeline signaling table may include information representing atimestamp format for a base timeline. The above information may bereferred to as an origine_timestamp_format field.

According to an embodiment, the origin_timestamp_format field mayrepresent that a timestamp of a basic timeline is a format of a mediatime. According to a specific embodiment, the broadcast transmissiondevice may set the origin_timestamp_format field to 0x00 to representthat the timestamp format of a corresponding basic timeline is a mediatime format.

According to another embodiment, the origin_timestamp_format field mayrepresent that a timestamp of a basic timeline is a format of an NTP.According to a specific embodiment, the broadcast transmission devicemay set the origin_timestamp_format field to 0x01 to represent that thetimestamp format of a corresponding basic timeline is an NTP format.

According to another embodiment, the origin_timestamp_format field mayrepresent that a timestamp of a basic timeline is a format of aprecision time protocol (PTP). According to a specific embodiment, thebroadcast transmission device may set the timestamp_format field to 0x02to represent that the timestamp format of a corresponding basic timelineis a PTP format.

According to another embodiment, the origin_timestamp_format field mayrepresent that a timestamp of a basic timeline is a format of atimecode. According to a specific embodiment, the broadcast transmissiondevice may set the origin_timestamp_format field to 0x03 to representthat the timestamp format of a corresponding basic timeline is atimecode format.

Additionally, according to an embodiment of the present invention, thetimeline signaling table may include information on whether includinglocation information on services and content components relating to abasic timeline that is a timeline mapping reference. The aboveinformation may be referred to as an origin_location_flag field.According to an embodiment, when the origin_location_flag field is setto a value other than 0, a timeline AU may include at least one of anorigin_location_length field and an origin_location field.

Additionally, according to an embodiment of the present invention, thetimeline signaling table may include location information on a serviceor content relating to a basic timeline. The above information may bereferred to as an origin_location field. According to a specificembodiment, information in the origin_location field may be an IPaddress, a port number, or a URI form.

Additionally, according to an embodiment of the present invention, thetimeline signaling table may include length information of positioninformation on a service or content relating to a basic timeline. Theabove information may be referred to as an origin_location_length field.According to a specific embodiment of the present invention, theorigin_location_length field may be an 8-bit field.

Additionally, according to an embodiment of the present invention, whena basic timeline that the reference of timeline mapping is a format of amedia time, the timeline signaling table may include information of anavailable time scale. The above information may be referred to as anorigin_timescale field. For example, in the case of MPEG-2 TS, the timescale may represent 9000 Hz. According to a specific embodiment of thepresent invention, the origin_timescale field may be a 32-bit field.

Additionally, according to an embodiment of the present invention, thetimeline signaling table may include media time information on a basictimeline. The above information may be referred to as anorigin_media_time field. Moreover, the origin_media_time field may meandifferently according to origin_timestamp_type. For example, whenorigin_timestamp_type means PTS, the origin_media_time field mayrepresent a presentation time. For example, when origin_timestamp_typemeans DTS, the origin_media_time field may represent a decoding time.According to a specific embodiment, the origin_media_time field may be32 bits when the origin_timestamp_version field is set to 0 and may be64 bits when the origin_timestamp_version field is set to 1.

Additionally, according to an embodiment of the present invention, thetimeline signaling table may include timestamp type information of abasic timeline. The above information may be referred to as anorigin_timestamp field. The basic timeline timestamp information mayrepresent different formats of timestamps according to a value of theorigin_timestamp_format field. Additionally, the basic timelinetimestamp information may represent different meanings according to avalue of the origin_timestamp_type field. For example, whenorigin_timestamp_type signals PTS, the basic timeline timestampinformation may represent a presentation time.

For example, when the origin_timestamp_type field represents DTS and theorigin_timestamp_format field is 0x01, the correspondingorigin_timestamp field may represent a decoding time expressed in NTP.According to a specific embodiment, the origin_timestamp field may be 32bits when the origin_timestamp_version field is set to 0 and may be 64bits when the origin_timestamp_version field is set to 1.

According to an embodiment, when the origin_timestamp_format fieldrepresents reserved, a timeline AU may include at least one of aprivate_data_length field and a private_data_bytes( ) field.

The private_data_length field may represent the byte unit length of theprivate_data_bytes( ) field. According to a specific embodiment of thepresent invention, the private_data_length field may be a 16-bit field.

The private_data_bytes( ) field may define by the length that theprivate_data_length field represents or may include future expansioncontent.

FIG. 111 is a view illustrating a configuration of payload data in whichone metadata is packetized in payload data of a transport packet.According to an embodiment, the payload data may include metadata andthe metadata may include media stream related timeline data.Additionally, according to an embodiment, when a broadcasts transmissiondevice uses a packet of a fixed length in a transport protocol, payloaddata may include a padding bit additionally.

FIG. 112 is a view when payload data of a transport packet includesmetadata for a timeline according to an embodiment of the presentinvention.

As shown in FIG. 112, according to an embodiment, the payload header mayinclude at least one of an F field, a Priority field, and a Type field.

According to an embodiment, a broadcast transmission device may set theF field to a value representing there is no error or syntax violation ina payload. In more detail, the broadcast transmission device may set theF field to 0. Additionally, the broadcast transmission device may setthe Priority field to a value representing the highest priority aspayload data includes all important data of a media file configuration.In more detail, the broadcast transmission device may set the Priorityfield to 0x00. Additionally, the broadcast transmission device may setthe Type field to a value representing information including metadata oftimeline information in a payload. In more detail, the broadcasttransmission device may set the Type field to 0x03. Additionally, themetadata may include the syntax of FIG. 110.

FIG. 113 is a view when a plurality of metadata are packetized in onetransport packet.

As shown in FIG. 113, the case that one transport packet includes aplurality of metadata may be referred to as an aggregation packet.According to an embodiment, the payload data may include a plurality ofaggregation units.

According to an embodiment, the aggregation unit may include informationrepresenting the length of metadata. According to another embodiment,when there is a metadata header field additionally, the aggregation unitmay include information on the sum of a metadata header field and ametadata field length. The above information may be referred to as ametadata length field.

FIG. 114 is a view when one transport packet includes several timelineinformation. In more detail, FIG. 114 illustrates the case that onetransport packet includes a plurality of timeline information havingdifferent references in relation to one media stream. According to anembodiment, a transport packet may include a payload header and acontent of the payload header is identical to that of FIG. 113.

Additionally, according to an embodiment, the payload data may includetwo aggregation units. However, the number of aggregation units inpayload data may be two or more.

According to an embodiment, as shown in FIG. 113, each aggregation unitmay include at least one of a metadata length field, a metadata headerfield, and a metadata field including timeline information.

However, the first aggregation unit shown in FIG. 114 may include ametadata field including a first timeline and the second aggregationunit may include a metadata field including a second timeline. Accordingto a specific embodiment, each timeline may have data based on differentreferences. For example, the first timeline may have data based on amedia time and the second timeline may have data based on NTP.

FIG. 115 is a view illustrating a packet payload in which one metadatais divided and packetized in a plurality of transport packets.

According to an embodiment, when the length of one metadata is greaterthan the length of a transport packet, in this case, a broadcasttransmission device may divide corresponding metadata in severaltransport packets and may then transmit them. As shown in FIG. 115, atransport packet may include at least one of a payload header, ametadata fragment header, and a metadata fragment. Additionally, when atransport protocol uses a packet of a fixed length, a transport packetmay include padding bits.

As shown in FIG. 115, according town embodiment, a metadata fragmentheader may include information representing whether a metadata fragmentin payload data of a corresponding transport packet includes the startpart of entire metadata. In more detail, the start part data may be partof entire data including the first bit of entire media data. The aboveinformation may be referred to as a start bit field. According to aspecific embodiment of the present invention, the start bit field may bea 1-bit field. According to an embodiment, the broadcast transmissiondevice may set start bit to 1 when a metadata fragment in acorresponding transport packet includes the start part of entiremetadata.

According to another embodiment, a metadata fragment header may includeinformation representing whether a metadata fragment in payload data ofa corresponding transport packet includes the end part of entiremetadata. In more detail, the end part data may be part of entire dataincluding the end bit of entire media data. The above information may bereferred to as an end bit field. According to a specific embodiment ofthe present invention, the end bit field may be a 1-bit field. Accordingto an embodiment, the broadcast transmission device may set end bit to 1when a metadata fragment in a corresponding transport packet includesthe end part of entire metadata.

According to another embodiment, the metadata header may includeinformation representing a metadata type. The above information may bereferred to as a metadata type field. According to a specificembodiment, the metadata type may represent that a correspondingmetadata fragment includes timeline information. In this case, thebroadcast transmission device may set the metadata type field to 0x00.According to another embodiment, the metadata type may represent that acorresponding metadata fragment includes metadata relating to labeling.In this case, the broadcast transmission device may set the metadatatype field to 0x01. According to a specific embodiment of the presentinvention, the metadata type field may be a 5-bit field.

FIG. 116 is a view illustrating a metadata fragment header according toanother embodiment of the present invention. Hereinafter, descriptionfor the same content as that of FIG. 115 is omitted.

According to an embodiment of the present invention, a metadata fragmentheader may include information representing the order of a metadatafragment in a corresponding packet payload. The above information may bereferred to as a Fragmentation number field. The broadcast receptiondevice 100 may determine which number metadata is included in acorresponding packet on the basis of metadata fragment order informationin a packet payload.

FIG. 117 is a view illustrating an operation when a broadcast receptiondevice receives a broadcast packet according to an embodiment of thepresent invention.

When it is determined that the data in the payload is not the media datain operation S205 of FIG. 43, the control unit 150 of the broadcastreception device 100 determines whether entire metadata is included onetransport packet in operation S301. In more detail, the control unit 150may determine that data in a payload is not metadata instead of mediadata from payload header information. Then, the control unit 150 maydetermine whether corresponding entire metadata is included in onetransport packet and transmitted. As mentioned above, one or moredifferent metadata may be included in one transport packet. Or, onemetadata is divided and included in a plurality of different transportpackets.

According to an embodiment of the present invention, when the controlunit 150 of the broadcast reception device 100 determines that entiremetadata is included in one transport packet, the control unit 150extracts metadata from one packet payload in operation S303. In moredetail, the control unit 150 extracts a payload header and extractsmetadata on the basis of the extracted payload header. According to anembodiment, the control unit 150 may extract one metadata from onepacket payload. Moreover, according to another embodiment, the controlunit 150 may extract a plurality of metadata from one packet payload.According to another embodiment of the present invention, the controlunit 150 of the broadcast reception device 100 may determine that onemetadata is divided and included in a plurality of transport packets. Inthis case, the control unit 150 extracts metadata from a plurality ofpackets payloads in operation 5305. According to a specific embodiment,one metadata may be divided and packetized in a plurality of transportpackets. The control unit 150 of the broadcast reception device 100obtains metadata signaling data from a packet payload. Then, the controlunit 150 may extract metadata from a plurality of packet payloads on thebasis of the obtained signaling data.

The control unit 150 of the broadcast reception device 100 providescontent on the basis of the extracted metadata in operation S307.According to a specific embodiment, the control unit 150 may obtain thepresentation or decoding time information of a content from metadata.According to another embodiment, the control unit 150 may obtain contentdescribing information from metadata.

FIG. 118 is a view when video stream is transmitted using RTP throughbroadcast network and video stream is transmitted using file formatbased media data through an internet network. In this case, afterreceiving an RTP packet or IP/UDP packet including timeline relatedmetadata, the broadcast reception device 100 may allow decoding andpresentation between related streams by matching an RTP protocol basedvideo stream and a DASH based video stream.

As mentioned above, a conventional broadcast transmission device loadstime information relating to the presentation of data (or object)included in a transport packet into a payload and transmits the payload.Or, the broadcast transmission device transmits additional signaling fortransmitting time information. In the case of a conventional method,since time information is loaded into an additional transport packet orpacket payload, the capacity of a packet header or the capacity of atransport become small relatively. However, in the case of aconventional method, since time information is transmitted through apacket separated from data to be transmitted, effectiveness may bereduced in terms of accurate and fast synchronization.

On the other hand, an embodiment of the present invention includes timeinformation relating to the decoding or presentation of a correspondingpacket in the packet header of a transport packet for supporting realtime content. Accordingly, since time information of a correspondingpacket is included in the header of a corresponding packet, compared toa conventional method, relatively accurate and fast synchronization ispossible. Especially, according to an embodiment of the presentinvention, suggested is a content of packetizing a transport packet bysetting the time information relating to decoding or presentation in theheader extension in the packet header. Herein, the header extension maybe part of the packet header including a selective header field that isnot essential or has a changeable size. Or, a transport packet may begenerated based on an object and accordingly, the object may be a targetto be transmitted through a transport packet. The object may be includedin a session and transmitted.

FIG. 119 is a view illustrating a configuration of a transport packetaccording to an embodiment of the present invention. The transportpacket shown in FIG. 119 may use a transport protocol for supportingreliable data transmission. According to a specific embodiment, areliable data transmission protocol may be Asynchronous Layered Coding(ALC). According to another embodiment, a reliable data transmissionprotocol may be Layered Coding Transport (LCT).

A packet header according to an embodiment of the present invention mayinclude version information of a packet. In more detail, the packetheader may include version information of a transport packet using acorresponding transport protocol. According to a specific embodiment,the information may be a V field. Additionally, the V field may be a4-bit field.

Additionally, a packet header according to an embodiment of the presentinvention may include information relating to the length of informationfor congestion control. In more detail, the packet header may includemultiple information relating to the multiplication of the length ofinformation for congestion control and a base unit thereof.

According to a specific embodiment, the information may be a C field.According to an embodiment, the C field may be set to 0x00 and in thiscase, represents that the length of information for congestion controlis 32 bits. According to another embodiment, the C field may be set to0x01 and in this case, represents that the length of information forcongestion control is 64 bits. According to another embodiment, the Cfield may be set to 0x02 and in this case, represents that the length ofinformation for congestion control is 96 bits. According to anotherembodiment, the C field may be set to 0x03 and in this case, representsthat the length of information for congestion control is 128 bits. The Cfield may be a 2 bit field.

Additionally, a packet header according to an embodiment of the presentinvention may include information specified for protocol. According to aspecific embodiment, the information may be a PSI field. Additionally,the PSI field may be a 2-bit field.

Additionally, a packet header according to an embodiment of the presentinvention may include information relating to the length of a fieldrepresenting identification information of a transport session. In moredetail, the packet header may include multiple information of a fieldrepresenting identification information of a transport session. Theabove information may be referred to as an S field. The S field may be a1 bit field.

Additionally, a packet header according to an embodiment of the presentinvention may include information relating to the length of a fieldrepresenting identification information of a transport object. In moredetail, the packet header may include multiple information multiplied tothe base length of a field representing identification information of atransport object. The above information may be referred to as an Ofield. The O field may be a 2 bit field.

Additionally, a packet header according to an embodiment of the presentinvention may include additional information relating to the length of afield representing identification information of a transport session.Then, the packet header may include additional information relating tothe length of a field representing identification information of atransport object. The additional information may be information onwhether to add half-word. Since a field representing identificationinformation of a transport packet and a field representingidentification information of a transport object should exist, the Sfield and the H field, or the O field and the H field cannot representzero at the same time.

Additionally, a packet header according to an embodiment of the presentinvention may include information representing that a session isterminated or the end is imminent. The above information may be referredto as an A field. According to a specific embodiment, when the A fieldrepresents session termination or imminent end, it may be set to 1.Accordingly, in typical cases, the A field may be set to 0. When abroadcast transmission device set the A field to 1, it represents thatthe last packet is transmitted through a session. When the A field isset to 1, the broadcast transmission device may need to maintain the Afield as 1 until all packets following a corresponding packet aretransmitted completely. Additionally, when the A field is set to 1, abroadcast reception device may recognize that the broadcast transmissiondevice stops packet transmission through a session immediately. That is,when the A field is set to 1, the broadcast reception device mayrecognize that there is no more packet transmission through a session.According to an embodiment, the A field may be a 1-bit field.

Additionally, a packet header according to an embodiment of the presentinvention may include information representing that object transmissionis terminated or the end is imminent. The above information may bereferred to as a B field. According to a specific embodiment, whenobject transmission termination is imminent, a broadcast transmissiondevice may set the B field to 1. Accordingly, in typical cases, the Bfield may be set to 0. When information for identifying a transportobject is not in a transport packet, the B field may be set to 1. Then,it may represent that object transmission termination in a sessionidentified by out-of-band information is imminent. Or, when the lastpacket for an object is transmitted, the B field may be set to 1. Or,when the last packet for an object is transmitted, the B field may beset to 1. When the B field of a packet for a specific object is set to1, the broadcast transmission device may need to set the B field to 1until the transmission of packets following a corresponding packet isterminated. Additionally, when the B field is set to 1, a broadcastreception device 100 may recognize that the broadcast transmissiondevice is to stop the transmission of a packet for object. That is, thebroadcast reception device 100 may recognize that there is no moreobject transmission through a session from the B field set to 1.According to an embodiment, the B field may be a 1-bit field.

Additionally, a packet header according to an embodiment of the presentinvention may include information representing the total length of aheader. The above information may be referred to as an HDR_LEN field.The HDR_LEN field may be a 32 multiple bit field. According to aspecific embodiment, when HDR_LEN field is set to 5, the total length ofa packet header may be 160 bits that are five multiples of 32.Additionally, the HDR_LEN field may be an 8-bit field.

Additionally, a packet header according to an embodiment of the presentinvention may include information relating to encoding or decoding of apayload included in a corresponding packet. The above information may bereferred to as a Codepoint field. According to an embodiment, theCodepoint field may be an 8-bit field.

Additionally, a packet header according to an embodiment of the presentinvention may include information for congestion control. The aboveinformation may be referred to as a Congestion Control Information (CCI)field. According to a specific embodiment, the CCI field may include atleast one of a Current time slot index (CTSI) field, a channel numberfield, and a packet sequence number field.

Additionally, a packet header according to an embodiment of the presentinvention may include information for identifying a transport session.The above information may be a Transport Session Identifier (TSI).Additionally, a field in a packet header including TSI information maybe referred to as a TSI field.

Additionally, a packet header according to an embodiment of the presentinvention may include information for identifying an object transmittedthrough a transport session. The above information may be a TransportObject Identifier (TOI). Additionally, a field in a packet headerincluding TOI information may be referred to as a TOI field.

Additionally, a packet header according to an embodiment of the presentinvention may include information for transmitting additionalinformation. The above information may be referred to as a HeaderExtension field. According to an embodiment, the additional informationmay be time information relating to the presentation of a transportobject. According to another embodiment, the additional information maybe time information relating to the decoding of a transport object.

Additionally, a packet header according to an embodiment of the presentinvention may include payload identification information. According toan embodiment, the identification information may be payloadidentification information relating to a Forward Error Correction (FEC)scheme. Herein, the FEC may be one type of payload format defined in RFC5109. The FEC may be used in RTP or SRTP. The above information may bereferred to as an FEC Payload ID field.

According to an embodiment, the FEC Payload ID field may includeinformation for identifying a source block of an object. The aboveinformation may be referred to as a Source block number field. Forexample, when the Source block number field is set to N, source blocksin an object may be numbered with 0 to N−1.

According to another embodiment, the FEC Payload ID field may includeinformation for identifying a specific encoding symbol. The aboveinformation may be referred to as an Encoding symbol ID field.

Additionally, a transport packet according to an embodiment of thepresent invention may include data in a payload. The field includingdata may be referred to as an Encoding symbol(s) field. According to anembodiment, the broadcast reception device 100 may reconfigure an objectby extracting the Encoding symbol(s) field. In more detail, data in theEncoding symbol(s) field may be generated from a source blocktransmitted through a packet payload.

FIG. 120 is a view illustrating a configuration of a packet headeraccording to an embodiment of the present invention.

In order to support the transmission of real time content, it iseffective that a transport packet received by the broadcast receptiondevice 100 includes property information of a packet and timinginformation relating to decoding or presentation. Accordingly, in orderto solve the above issue, as shown in FIG. 120, a packet header may beconfigured.

The packet header of FIG. 120 has a configuration mostly similar to thatof the packet header of FIG. 119. Therefore, description of the sameparts will be omitted.

A packet header according to an embodiment of the present invention mayinclude information representing the type of an object for transmission.The above information may be referred to as a type field. The type fieldmay be a 2 bit field.

According to a specific embodiment, the type field may represent thatthe type of an object for transmission is a regular file. Herein, theregular file may be an ISO BMFF based media file. In more detail, theregular file may be obtained by encapsulating a media file in ISO BMFFformat. In this case, the type field may be set to 01₍₂₎. According toanother embodiment, the type field may represent that the type of anobject for transmission is an HTTP entity type. In this case, the typefield may be set to 10₍₂₎. According to another embodiment, the typefield may represent that the type of an object for transmission is anaudio access unit or a video access unit. Additionally, the type fieldmay represent that an object type is a network abstract layer (NAL)unit. In this case, the type field may be set to 11₍₂₎.

Additionally, a packet header according to an embodiment of the presentinvention may represent that a corresponding transport packet includesthe first part or end part of a transport object. Informationrepresenting that a transport packet includes the first part or end partof a transport object may be a marker bit. According to a specificembodiment, the marker bit may be an M field. In more detail, the Mfield may be interpreted differently according to a value of the typefield. For example, when the type of an object for transmission is afile, it may represent that a corresponding transport packet includesthe end part of a file. Herein, the end part is part including the lastbit of a file. For another example, when the type of an object fortransmission is Audio or Video (AV) data, it may represent that acorresponding transport packet includes the first or last bit of anaccess unit.

FIGS. 121 and 122 are views illustrating a configuration of a headerextension including time information. The header extension shown inFIGS. 121 and 122 may included in the header extension field shown inFIG. 120.

As shown in FIG. 121, a header extension according to an embodiment ofthe present invention may include type information of a headerextension. The above information may be referred to as a HeaderExtension Type (HET) field.

Additionally, a header extension according to an embodiment of thepresent invention may include the length information of the headerextension. The above information may be referred to as a HeaderExtension length (HEL) field.

Additionally, a header extension according to an embodiment of thepresent invention may represent the current time of a broadcasttransmission device. That is, the header extension may includecorresponding packet transmission time information of a broadcasttransmission device. For example, the broadcast transmission device maybe a server. According to a specific embodiment, informationrepresenting the current time of a broadcast transmission device may bea Sender Current Time (SCT) field.

Additionally, a header extension according to an embodiment of thepresent invention may represent whether the SCT field is a 64 bit field.In more detail, the header extension may represent whether the SCT fieldis included in a header extension configured with 64 bits. According toa specific embodiment, information representing whether the SCT field is64 bits may be an SCT Hi field.

Additionally, a header extension according to an embodiment of thepresent invention may represent whether the SCT field is a 32 bit field.In more detail, the header extension may represent whether the SCT fieldis included in a header extension configured with 32 bits. According toa specific embodiment, information representing whether the SCT field is32 bits may be an SCT Low field.

Additionally, a header extension according to an embodiment of thepresent invention may include expected residual time information of anobject for transmission. The above information may be an ExpectedResidual Time (ERT) field.

Additionally, a header extension according to an embodiment of thepresent invention may represent whether the ERT field exits in acorresponding packet. Corresponding information may be an ERT flagfield.

Additionally, a header extension according to an embodiment of thepresent invention may include information on a time at which a sessionis changed lastly. The above information may be an SLC field.

Additionally, a header extension according to an embodiment of thepresent invention may represent whether the SLC field exits in acorresponding packet. Corresponding information may be an SLC flagfield.

Additionally, a header extension according to an embodiment of thepresent invention may include a field extended and used according to atransport protocol that a broadcast transmission device uses.Corresponding information may be a PI-specific Use field.

FIG. 122 is a view illustrating a header extension having an addedconfiguration according to another embodiment of the present invention.

A header extension according to another embodiment of the presentinvention may include timing information of data included in a packetpayload. The above information may be a Timestamp field. For example,the Timestamp field may include information on a time point at which thefirst byte of data included in a packet payload is decoded. For anotherexample, the Timestamp field may include information on a presentationtime point of data. Furthermore, the Timestamp field may includetimescale information or timescale based timing information. Herein, thetimescale information may be a unit representing a time for a decodingor presentation time point of a transport object. In the case oftimescale based timing information, the broadcast reception device mayobtain information a decoding or presentation time point by multiplyinga value of the Timestamp field and a timescale.

A header extension according to another embodiment of the presentinvention may include format information of a Timestamp field. The aboveinformation may be a TS format field. According to a specificembodiment, the TS format field may represent that timing informationincluded in a transport packet is in the format of media time. The mediatime is a media presentation time according to an arbitrary mediatimeline. In this case, the TS format field may be set to 0x01.Additionally, the TS format field may represent that timing informationincluded in a transport packet is in the format of Network Time Protocol(NTP). In this case, the TS format field may be set to 0x02.Additionally, the TS format field may represent that timing informationincluded in a transport packet is in the format of normal playing time.The format of normal playing time may be a playing time expressedrelative from a presentation start time point and may be expressed inhour, minute, second, or second decimal point unit. In this case, the TSformat field may be set to 0x03. Additionally, the TS format field mayrepresent that timing information included in a transport packet is inthe format of SMPTE time code. Society of Motion Picture and TelevisionEngineers (SMPTE) time code is time code defined in SMPTE. In moredetail, the SMPTE time code may be a time information format defined forindividual frame labeling of video in SMPTE. In this case, the TS formatfield may be set to 0x04. Additionally, the TS format field mayrepresent that timing information included in a transport packet is 90KHz timing information. In this case, the TS format field may be set to0x05.

A header extension according to another embodiment of the presentinvention may represent a configuration of a timestamp field.Information representing a configuration of timing information may bereferred to as a TS version field. For example, the TS version field mayrepresent that the timestamp field is a 32 bit field. In this case, theTS version field may be set to 0. For another example, the TS versionfield may represent that the timestamp field is a 64 bit field. In thiscase, the TS version field may be set to 1.

FIGS. 123 to 126 are views illustrating a configuration of a headerextension according to another embodiment of the present invention. Inmore detail, the header extension structure shown in FIGS. 123 to 126may include at least one of object type information and timinginformation for transmission. Additionally, a corresponding headerextension structure may be included in a header extension field (headerextension). Additionally, it may be used as part of a packet headertransmitting content.

As shown in FIG. 123, a structure (EXT_OBJ_INFO) of a header extensionaccording to another embodiment of the present invention may includetype information of header extension part. The above type informationmay be referred to as an HET field. Additionally, the header extensionstructure may include length information of header extension part. Theabove length information may be referred to as an HEL field.Additionally, the header extension structure may include typeinformation of a transport object. The above object type information maybe referred to as an Object type field.

In a specific embodiment, the Object type field may represent that atransport object is the type of a regular file. Herein, the regular filemay be an ISO BMFF based media file. In more detail, the regular filemay be obtained by encapsulating a media file in ISO BMFF format. Inthis case, the Object type field may be set to 0x01. According toanother embodiment, the Object type field may represent that a transportobject is the type of an HTTP entity type. In this case, the Object typefield may be set to 0x02. According to another embodiment, the Objecttype field may represent that a transport object is an audio data type.The Object type field may represent that a transport object is an AACbased audio data type. At this point, the AAC based audio data type maybe audio data encoded through AAC. In this case, the Object type fieldmay be set to 0x03. According to another embodiment, the Object typefield may represent that a transport object is an audio data type. Inmore detail, the Object type field may represent that a transport objectis an H.264 type. In this case, the Object type field may be set to0x04. According to another embodiment, the Object type field mayrepresent that a transport object is an HEVC based video data type. Atthis point, the HEVC based video data type may be encoded video dataencoded through HEVC. In this case, the Object type field may be set to0x05. According to another embodiment, the Object type field mayrepresent that a transport object is an ISO BMFF based file type. Inthis case, the Object type field may be set to 0x06. According toanother embodiment, the Object type field may represent that a transportobject is metadata. In this case, the Object type field may be set to0x07.

Additionally, a structure (EXT_OBJ_INFO) of a header extension accordingto another embodiment of the present invention may represent that acorresponding transport packet includes the first part or end part of atransport object. Information representing that a transport packetincludes the first part or end part of a transport object may be amarker bit. According to a specific embodiment, the marker bit may be anM field. The M field may be interpreted differently according to a valueof the Object type field. For example, when the type of an object fortransmission is a file, it may represent that a corresponding transportpacket includes the end part of a file. Herein, the end part is partincluding the last bit of a file. For another example, when the type ofan object for transmission is Audio or Video (AV) data, it may representthat a corresponding transport packet includes the first or last bit ofan access unit.

Additionally, a structure (EXT_OBJ_INFO) of a header extension accordingto another embodiment of the present invention may include timinginformation of data included in a packet payload. The above informationmay be a Timestamp field. For example, the Timestamp field may includeinformation on a time at which the first byte of data included in apacket payload is decoded. For another example, the Timestamp field mayinclude information on a presentation time of data. Furthermore, theTimestamp field may include timescale information or timescale basedtiming information. Herein, the timescale information may be a unitrepresenting a time for a decoding or presentation time point of atransport object. In the case of the timescale based timing information,a broadcast reception device may obtain information on a decoding orpresentation time point by multiplying the value of the Timestamp fieldby a timescale.

FIG. 124 is a view illustrating some configurations added to the headerextension structure of FIG. 123 according to another embodiment of thepresent invention.

As shown in FIG. 124, the header extension structure may representwhether a timestamp field exists in a corresponding header structure.Information representing whether the Timestamp field exists may bereferred to as a TS flag field. In a specific embodiment, when the TSflag field is set to 1, it may represent that the timestamp field existsin a corresponding header structure.

Additionally, a structure of a header extension according to anotherembodiment of the present invention may include format information of aTimestamp field. The above information may be a TS format field.According to a specific embodiment, the TS format field may representthat timing information included in a transport packet is in the formatof media time. The media time may be a media presentation time accordingto an arbitrary media timeline. In this case, the TS format field may beset to 0x01. Additionally, the TS format field may represent that timinginformation included in a transport packet is in the format of NetworkTime Protocol (NTP). In this case, the TS format field may be set to0x02. Additionally, the TS format field may represent that timinginformation included in a transport packet is in the format of a normalplaying time. The format of a normal playing time may be a presentationtime expressed relative from a presentation start time point and may beexpressed in hour, minute, second, or second decimal point unit In thiscase, the TS format field may be set to 0x03. Additionally, the TSformat field may represent that timing information included in atransport packet is in the format of SMPTE time code. The SMPTE timecode is time code defined in Society of motion picture and televisionengineers (SMPTE). In this case, the TS format field may be set to 0x04.Additionally, the TS format field may represent that timing informationincluded in a transport packet is 90 KHz timing information. In thiscase, the TS format field may be set to 0x05.

Additionally, a structure of a header extension according to anotherembodiment of the present invention may represent a configuration of atimestamp field. In more detail, a structure of a header extension mayrepresent a configuration of timing information relating to objectpresentation or decoding included in the timestamp field. The aboveinformation may be referred to as a TS version field. For example, theTS version field may represent that the timestamp field is a 32 bitfield. In this case, the TS version field may be set to 0. For anotherexample, the TS version field may represent that the timestamp field isa 64 bit field. In this case, the TS version field may be set to 1.

FIG. 125 is a view illustrating some configurations added to the headerextension structure of FIG. 123 according to another embodiment of thepresent invention.

As shown in FIG. 125, a structure of a header extension according toanother embodiment of the present invention may include additionalinformation relating to a transport object. According to a specificembodiment, a structure of a header extension may include locationinformation of an object. For example, the location information of anobject may represent URL information of an ISO BMFF based segment. Inmore detail, the location information of an object may represent URLinformation through which ISO BMFF based segments are downloaded. Inthis case, additional information relating to a transport object may bereferred to as an Extension field.

Additionally, a structure of a header extension according to anotherembodiment of the present invention may represent whether an Extensionfield exists in a corresponding header extension structure. In thiscase, Information representing whether the Extension field exists may bereferred to as an Ext Flag field.

FIG. 126 is a view when a new header extension structure is used as partof a packet header according to an embodiment of the present invention.As shown in FIG. 126, the part of the packet header may include timinginformation of a transport object. The part of the packet headerincluding timing information of a transport object may be anEXT_MEDIA_TIME field.

The EXT_MEDIA_TIME field may include timing information of data includedin a packet payload. The above information may be a Timestamp field. Forexample, the Timestamp field may include information on a time at whichthe first byte of data included in a packet payload is decoded. Foranother example, the Timestamp field may include information on apresentation time of data. Furthermore, the Timestamp field may includetimescale information or timescale based timing information. Herein, thetimescale information may be a unit representing a time for a decodingor presentation time point of a transport object. In the case of thetimescale based timing information, a broadcast reception device mayobtain information on a decoding or presentation time point bymultiplying the value of the Timestamp field by a timescale.

Additionally, the EXT_MEDIA_TIME field may include format information ofa Timestamp field. The above information may be a TS format field.According to a specific embodiment, the TS format field may representthat timing information included in a transport packet is in the formatof media time. In this case, the TS format field may be set to 0x01.Additionally, the TS format field may represent that timing informationincluded in a transport packet is in the format of Network Time Protocol(NTP). In this case, the TS format field may be set to 0x02.Additionally, the TS format field may represent that timing informationincluded in a transport packet is in the format of normal playing time.In this case, the TS format field may be set to 0x03. Additionally, theTS format field may represent that timing information included in atransport packet is in the format of SMPTE time code. The SMPTE timecode is time code defined in Society of motion picture and televisionengineers (SMPTE). In this case, the TS format field may be set to 0x04.Additionally, the TS format field may represent that timing informationincluded in a transport packet is 90 KHz timing information. In thiscase, the TS format field may be set to 0x05. Additionally, the TSformat field may represent that timing information included in atransport packet is in a GPS time format. In this case, the TS formatfield may be set to 0x06.

Additionally, the EXT_MEDIA_TIME field may represent a configuration ofa Timestamp field. A structure of a header extension may represent aconfiguration of timing information relating to object presentation ordecoding included in the timestamp field. The above information may bereferred to as a TS version field. For example, the TS version field mayrepresent that the timestamp field is a 32 bit field. In this case, theTS version field may be set to 0. For another example, the TS versionfield may represent that the timestamp field is a 64 bit field. In thiscase, the TS version field may be set to 1.

Additionally, the EXT_MEDIA_TIME field may include additionalinformation relating to timing information. For example, datainformation relating to timing information to be mapped may be included.The additional information relating to timing information may bereferred to as an Extension field.

Additionally, the EXT_MEDIA_TIME field may include information on aconfiguration of the Extension field. In more detail, variousinformation may be included in the Extension field and flags may form aset in various information. In this case, a set of flags may be referredto as an Ext Flags field.

A transport object that the broadcast reception device 100 receivesthrough a broadcast reception unit may need to synchronize with timinginformation having a different format or reference time. In more detail,the broadcast reception device 100 may need to synchronize timinginformation of a transport object with a base timeline that is thereference for synchronization having a different format or referencetime than timing information of a transport object. According to anembodiment, timing information for synchronization may be a presentationtiming of a transport object. Timing information for synchronizationaccording to another embodiment may be a decoding timing of a transportobject. In this case, a broadcast transmission device may need totransmit information on a mapping relationship between different timinginformation and timing information of a transport object to thebroadcast reception device 100. According to an embodiment of thepresent invention to solve the above issue, metadata including theabove-mentioned timeline_component_AU may be transmitted as onetransport object.

According to an embodiment of the present invention to solve the aboveissue, the above-mentioned header extension may include additionalmapping information different from timing information of a transportobject. In more detail, a header extension (EXT_TIME_MAP) may includeinformation for mapping a timestamp of a transport object into anothertimeline. For example, the broadcast reception device 100 may map apresentation time of a packet payload into a GPS time by using the aboveinformation through the control unit 150. In this case, the GPS time maybe a base timeline.

FIG. 127 is a view illustrating a structure of a header extension forsupporting mapping with another timing information according to anembodiment of the present invention.

As shown in FIG. 127, the header extension may include formatinformation of a Timestamp field. The above information may be a TSformat field. According to a specific embodiment, the TS format fieldmay represent that a timestamp included in a transport packet is in theformat of media time. In this case, the TS format field may be set to0x01. Additionally, the TS format field may represent that a timestampincluded in a transport packet is in the format of Network Time Protocol(NTP). In this case, the TS format field may be set to 0x02.Additionally, the TS format field may represent that a timestampincluded in a transport packet is in the format of normal playing time.In this case, the TS format field may be set to 0x03. Additionally, theTS format field may represent that a timestamp included in a transportpacket is in the format of SMPTE time code. The SMPTE time code is timecode defined in Society of motion picture and television engineers(SMPTE). In this case, the TS format field may be set to 0x04.Additionally, the TS format field may represent that a timestampincluded in a transport packet is a 90 KHz based timestamp. In thiscase, the TS format field may be set to 0x05. Additionally, the TSformat field may represent that a timestamp included in a transportpacket is in a GPS time format. In this case, the TS format field may beset to 0x06.

Additionally, the header extension may represent the version orconfiguration of a timestamp field. A structure of a header extensionmay represent a configuration of timing information relating to objectpresentation or decoding included in the timestamp field. The aboveinformation may be referred to as a TS version field. For example, theTS version field may represent that the timestamp field is a 32 bitfield. In this case, the TS version field may be set to 0. For anotherexample, the TS version field may represent that the timestamp field isa 64 bit field. In this case, the TS version field may be set to 1.

Additionally, the header extension may represent whether timinginformation of a time line into which a timestamp of a transport objectis mapped exists. In this case, information representing the presencemay be referred to as an OTS flag field. In a specific embodiment, whenthe OTS flag field is set to 1, it may represent that timing informationof a timeline into which a timestamp of a transport object is mappedexists.

Additionally, a header extension may represent a timestamp format of atime line into which a timestamp of a transport object is mapped. Inmore detail, a timestamp of a transport object may be at least one of apresentation time and a decoding time of an object. Additionally, atimeline in which a transport object is mapped into a timestamp may be abase timeline. Herein, the base timeline is a reference timeline forsynchronization between a plurality of different timelines.

The above information may be an OTS format field. According to aspecific embodiment, the OTS format field may represent that a timestampmapped into a timestamp of a transport object included in a transportpacket is in the format of a media time. In this case, the OTS formatfield may be set to 0x01. Additionally, the OTS format field mayrepresent that timing information included in a transport packet is inthe format of Network Time Protocol (NTP). In this case, the OTS formatfield may be set to 0x02. Additionally, the OTS format field mayrepresent that a timestamp mapped into a timestamp of a transport objectincluded in a transport packet is in the format of normal playing time.In this case, the OTS format field may be set to 0x03. Additionally, theOTS format field may represent that a timestamp mapped into a timestampof a transport object included in a transport packet is in the format ofSMPTE time code. The SMPTE time code is time code defined in Society ofmotion picture and television engineers (SMPTE). In this case, the OTSformat field may be set to 0x04. Additionally, the OTS format field mayrepresent that a timestamp mapped into a timestamp of a transport objectincluded in a transport packet is 90 KHz based timing information. Inthis case, the OTS format field may be set to 0x05. Additionally, theOTS format field may represent that a timestamp mapped into a timestampof a transport object included in a transport packet is in a GPS timeformat. In this case, the OTS format field may be set to 0x06.

Additionally, a header extension may represent a version orconfiguration of a timestamp of a timeline mapped into a timestamp of anobject and a timestamp of a transport object. In more detail, atimestamp of a transport object may be at least one of a presentationtime and a decoding time of an object. Additionally, a timeline in whicha transport object is mapped into a timestamp may be a base timeline.Herein, the base timeline is a reference timeline for synchronizationbetween a plurality of different timelines.

In this case, information representing a configuration or version of atimestamp mapped into a timestamp of a transport object may be referredto as an OTS version field. For example, the OTS version field mayrepresent that a timestamp mapped into a timestamp of a transport objectis 32 bits. In this case, the OTS version field may be set to 0. Foranother example, the OTS version field may represent that a timestampmapped into a timestamp of a transport object is 64 bits. In this case,the OTS version field may be set to 1.

Additionally, the header extension may represent whether locationinformation is included. In this case, information representing whetherlocation information is included may be a Location flag field. Forexample, when the Location flag field is set to 1, it may represent thatlocation information is included in a corresponding header extension.

Additionally, the header extension may include a timestamp of atransport object and timing information of a timeline mapped into thetimestamp of the transport object. The above information may be referredto as a timestamp field.

Additionally, the header extension may include a timestamp of acorresponding header extension and timing information relating to atransport object mapped into a timestamp of a transport object. Theabove information may be an Origin timestamp field.

Additionally, the header extension may include location information ofdata relating to a timeline mapped into a timestamp of an object. Theabove information may be referred to as a location field. In anembodiment, when mapping with a timeline of a specific ISO BMFF baseddata segment is required, the Location field may include the URL of acorresponding data segment.

FIG. 128 is a view illustrating a method of operating a broadcasttransmission device according to an embodiment of the present invention.

The broadcast transmission device obtains an object for transmissionthrough a control unit in operation S401. According to an embodiment,the object may be AV content. According to another embodiment, an objectmay be AV content related enhancement data.

The broadcast transmission device may obtain time information and formatinformation of an object through a control unit in operation 5403.According to an embodiment, the time information may be a timestamp of atransport object. According to another embodiment, the time informationmay be timing information of a timeline to be mapped into a timestamp ofa transport object. According to another embodiment, the timeinformation may be a timestamp of a header extension structure.According to another embodiment, the time information may be timinginformation of a transport object to be mapped into a timestamp of aheader extension structure. Additionally, the format information may beat least one of a regular file, an HTTP entity, and an audio/videoaccess unit.

In more detail, a timestamp of a transport object may be at least one ofa presentation time and a decoding time of an object. Additionally, atimeline in which a transport object is mapped into a timestamp may be abase timeline. Herein, the base timeline is a reference timeline forsynchronization between a plurality of different timelines. For example,the base timeline may be GPS time and information for synchronizing atransport object with the GPS time may be included in the above headerextension.

The broadcast transmission device sets the time information and formatinformation obtained through the control unit in a packet header andpacketizes a transport packet in operation S405. In more detail, acontrol unit of a broadcast transmission device packetizes a packetheader including the obtained time information and a packet payloadincluding data according to a transport protocol. According to anotherembodiment, the broadcast transmission device may set time informationand format information in a header extension that is selectivelyincluded in a packet header through the control unit.

In more detail, the time information may be information relating to apresentation time of an object. The information relating to apresentation time may be at least one of a presentation time point(timing information) and a decoding time point (timing information) of atransport object. According to another embodiment, the additionalinformation may be type information of a transport object. The broadcasttransmission device may set at least one of whether a header extensionexists in a packet header, the length of a header extension, and typeinformation of a header extension, in a normal packet header.

The broadcast transmission device transmits the packetized transportpacket through a transmission unit in operation S407. The transmissionunit may transmit a transport packet through at least one of aterrestrial broadcast network and an internet network.

FIG. 129 is a view illustrating a method of operating a broadcastreception device according to an embodiment of the present invention.

The broadcast reception device 100 receives a transport packet throughthe broadcast reception unit 110 in operation S411. As described withreference to FIG. 128, a transport packet may include a packet headerand a packet payload and the packet header may include a headerextension selectively.

The control unit 150 of the broadcast reception device 100 extracts apacket header and a header extension from the received transmissionpacket in operation 5412. According to a specific embodiment, thecontrol unit 150 may extract a packet header included in a transportpacket. Additionally, a header extension that is selectively included ina packet header may be extracted from a packet header.

The control unit 150 of the broadcast reception device 100 obtains atleast one of time information relating to a transport object and formatinformation of a transport object on the basis of a packet header inoperation 5413. According to another embodiment, the control unit 150may obtain at least one of the time information and the formatinformation from a header extension that is selectively included in apacket header. According to a specific embodiment, the control unit 150may obtain a timestamp of a transport object on the basis of a headerextension. Additionally, the control unit 150 may obtain formatinformation of a transport object. The format information of thetransport object may represent at least one of a regular file, an HTTPentity, and an audio/video access unit. Herein, the regular file may bean ISO BMFF based media file.

The control unit 150 of the broadcast reception device 100 determineswhether information for mapping into another time information isobtained from a packet header in operation S414. In more detail, thecontrol unit 150 determines whether another time information mappinginto time information for a corresponding transport object exists in apacket header. According to another embodiment, the control unit 150 maydetermine the other time information on the basis of specificinformation extracted from a header extension that is selectivelyincluded in a packet header.

According to an embodiment, when the control unit 150 determines thatinformation for mapping into another time information from a packetheader, it obtains information for mapping from the packet header inoperation S415. Herein, the other time information may be the abovementioned timing information of the base timeline. Additionally, thetiming information may include at least one of presentation timinginformation and decoding timing information of a transport object.According to a specific embodiment, the control unit 150 may obtaintiming information of a timeline mapped into a transport object on thebasis of a packet header. According to another embodiment, the controlunit 150 may obtain timing information of a transport object mapped intoa timestamp of a corresponding packet header on the basis of a packetheader. Additionally, the control unit 150 may obtain locationinformation of data mapped into a transport object on the basis of apacket header. According to another embodiment, the control unit 150 mayobtain information for mapping from a header extension that isselectively included in a packet header.

The control unit 150 of the broadcast reception device 100 obtains atransport object on the basis of the obtained time information inoperation S416. According to an embodiment, when the control unit 150does not obtain another time information and mapping information, itoutputs an object on the basis of a timestamp of a correspondingtransport object. According to another embodiment, when the control unit150 obtains the other time information and the mapping information, itoutputs an object on the basis of corresponding mapping information anda timestamp of an object.

FIG. 130 is a view illustrating a structure of a packet header includinginformation on a configuration of a transport packet.

A packet header according to an embodiment of the present invention mayrepresent that the first or end part data in an entire transport objectis included in a packet payload. In this case, Information representingthat the first or end part data is included may be a marker bit.According to a specific embodiment, the marker bit may be an M field.The M field may be a 1 bit field.

Additionally, a packet header according to an embodiment of the presentinvention may include information on a configuration of a correspondingtransport packet. In this case, the information on the configuration ofthe transport packet may be a type field. The type field may be a 2 bitfield.

In another case, the information on the configuration of the transportpacket may be included in a codepoint field. The Codepoint field may bean 8 bit field.

According to a specific embodiment, the Type field may represent that acorresponding transport object has a regular packet structure. In moredetail, it represents that a corresponding packet uses an existingtransport packet structure shown in FIG. 119 as it is. In this case, thetransport packet may include at least one of a packet header, a headerextension, a packet payload, an identifier, and data. Additionally, thebroadcast transmission device may set the Type field to 0x00.

Additionally, according to a specific embodiment, the Type field mayrepresent that a corresponding transport packet does not include apayload. In more detail, it represents that a corresponding transportpacket includes only a packet header and a header extension. In thiscase, the broadcast transmission device may set the type field to 0x01.

Additionally, according to a specific embodiment, the Type field mayrepresent that a corresponding transport packet includes offsetinformation for an entire transport object. Herein, the offsetinformation is offset information of data including an encoding symbolfield of a corresponding transport packet. That is, the offsetinformation represents offset information of data of a correspondingtransport packet in an entire transport object. At this point, accordingto an embodiment, a corresponding transport packet may have a structureand configuration identical to those of a regular transport packet butthe payload identifier field may be replaced with a data offset field.In this case, the broadcast transmission device may set the type fieldto 0x02.

Additionally, according to a specific embodiment, the Type field mayrepresent that a corresponding transport packet includes a differentconfiguration than a structure of an existing regular transport packet.In this case, the broadcast transmission device may set the type fieldto 0x03. According to a specific embodiment, the Type field mayrepresent that a corresponding transport object does not include apayload identifier field. In this case, the broadcast transmissiondevice may set the type field to 0x04. FIG. 131 is a view illustrating aconfiguration of the transport packet described with reference to FIG.130. As shown in FIG. 131, the Type field may represent a structure of atransport packet. However, the present invention is not limited to thetransport packet shown in FIG. 131 and also is not limited to the setvalue in FIG. 131.

FIG. 132 is a view illustrating a method of operating a broadcasttransmission device according to an embodiment of the present invention.

The broadcast transmission device obtains structure information of atransport packet through a control unit in operation S421. According toan embodiment, a structure of a transport packet may be an existingregular packet structure. According to another embodiment, a structureof a transport packet may have a structure configured with only a packetheader and a header extension. According to another embodiment, astructure of a transport packet may be a structure including aconfiguration that replaces an existing payload identifier. According toanother embodiment, a structure of a transport packet may be a structurenot including a payload identifier.

The broadcast transmission device packetizes a transport packet bysetting a value that represents information of a corresponding structurein a packet header on the basis of a structure of the transport packetobtained through the control unit in operation S423. In more detail, thecontrol unit may set information of a corresponding structure in theType field.

The broadcast transmission device transmits the packetized transportpacket through a transmission unit in operation S425. According to anembodiment, the transmission unit may transmit the packetized transportpacket through a terrestrial broadcast network. According to anotherembodiment, the transmission unit may transmit the packetized transportpacket through an internet network.

FIG. 133 is a view illustrating a method of operating a broadcastreception device according to an embodiment of the present invention.

The broadcast reception device 100 receives a transport packet throughthe broadcast reception unit 110 in operation S431. According to anembodiment, the broadcast reception unit 110 may receive a transportpacket through a terrestrial broadcast network. According to anotherembodiment, an IP communication unit 130 may receive a transport packetthrough an internet network.

The broadcast reception device 100 extracts a packet header from thereceived transport packet through the control unit 150 in operationS433. In more detail, the transport packet may include at least one of apacket header and a packet payload. Accordingly, the control unit 150may extract a packet header signaling a packet payload from a transportpacket.

The broadcast reception device 100 obtains configuration information ofa transport packet from the extracted packet header in operation S435.In more detail, the packet header may include information representing astructure of a transport packet. Accordingly, the broadcast receptiondevice 100 obtains information representing a structure of a transportpacket from a packet header through the control unit 150. According toan embodiment, a structure of a transport packet may be an existingregular transport packet structure. According to another embodiment, astructure of a transport packet may be a structure including only apacket header and a header extension. According to another embodiment, astructure of a transport packet may be a structure including offsetinformation that replaces a packet payload identifier. According toanother embodiment, a structure of a transport packet may be a structurenot including a packet payload identifier.

FIG. 134 is a view illustrating timeline reference information AUincluding suggested presentation delay (SPD) according to an embodimentof the present invention.

The present invention proposes insertion of SPD into the aforementionedtimeline reference information AU and transmission of the resultinginformation. In addition, the present invention proposes insertion ofSPD into the aforementioned LCT packet field and transmission of theresulting information. As such, a timeline of media streams transmittedthrough different networks (e.g., the Internet and a broadcast network)may be reconfigured and may be smoothly reproduced by a receiver. Inaddition, a timeline reference/timestamp to which the SPD is applied maybe transmitted no as to effectively support synchronization betweenreceivers present in different reception environments.

The SPD may refer to suggested presentation delay up to consumption timebased on generation time of a media stream transmitted through anexternal network or an internal network. In some embodiments, the SPDmay refer to suggested presentation delay to decoding time based onencoding time of a media stream. Alternatively, when a specific unit forenabling random access of a media stream accumulates on a broadcaststream, the SPD may refer to a time difference between time in which afirst byte of the corresponding unit accumulates and a last byte of thecorresponding unit accumulates. The corresponding data unit may includea random access point (RAP). Both time points as a reference of the SPDmay be changed in some embodiments. The SPD, that is, suggestedpresentation delay may be used to compensate for a difference betweenpresentation time periods according to a buffer time (BT) of a receiver.With regard to a plurality of receivers, respective practical networkbandwidths are different and, thus, a buffer time may be different foreach receiver. According to a buffer time difference, even if the samemedia data is broadcast by a transmitting side, presentation time of areceiver may be changed. This may be compensated for and the SPD may beapplied to a timeline reference or timestamp value so as to reproducethe same media at the same time for each receiver. In addition, when aspecific unit for enabling random access of a media stream istransmitted through a broadcast stream, the SPD may be used to inducefastest presentation time included in the corresponding unit. Thefastest presentation time included in the corresponding unit may beinduced in consideration of a presentation timestamp obtained byconsidering the SPD and sender current time of a server for generating apacket for carrying data, time in which a packet is actually received,and so on.

The SPD may be applied when a timeline of a media stream transmittedthrough an internal network or an external network is reconfigured usingthe timeline reference information AU. That is, when the timeline of aninternal network or an external network is reconfigured, an SPD valuemay be subtracted from the timeline reference value of the internalnetwork or the external network to configure the timeline to which thesuggested presentation delay is applied.

In addition, the SPD may be applied when a timestamp includinginformation of presentation time of corresponding media data istransmitted and synchronization is performed. That is, with regard tosynchronization using a timestamp, a value of the SPD may be added tothe timestamp value to perform synchronization to which suggestedpresentation delay is applied.

As described above, the timeline reference information AU may be usedfor synchronization between streams transmitted through differentnetworks. Here, the illustrated timeline reference information AU maycorrespond to another embodiment of the aforementioned timelinecomponent AU or timeline reference information AU.

Fields and structures of the timeline reference information AU includingSPD according to an embodiment of the present invention will bedescribed

An AU_identifier field may refer to the aforementioned AU_identifierinformation. That is, the AU_identifier field may identify correspondingtimeline reference information AU. In addition, the AU_identifier fieldmay also identify a structure of the corresponding timeline referenceinformation AU. In some embodiments, the AU_identifier field may have asize of 8 bits.

An AU_length field may refer to the aforementioned AU_lengthinformation. That is, the AU_length field may include length informationof the corresponding timeline reference information AU. In someembodiments, the corresponding field may have a size of 32 bits and haveuimsbf format.

An external_media_URL_flag field may refer to the aforementionedexternal_media_URL_flag information. The external_media_URL_flag fieldmay be a flag indicating whether the corresponding timeline referenceinformation AU has the external_media_URL field. That is, thecorresponding field may indicate whether URL information of a streamtransmitted through an external network is included in the timelinereference information AU. The corresponding field may have a size of 1bit and have bslbf format.

An internal_timeline_reference_flag field may refer to theaforementioned internal_timeline_reference_flag information. Theinternal timeline_reference_flag field may be a flag indicating whetherthe corresponding timeline reference information AU includes theinternal_timeline_reference field. That is, the corresponding field mayindicate whether timeline reference information of an internal networkis included in the timeline reference information AU. The correspondingfield may have a size of 1 bit and have bslbf format.

An external_timeline_reference_flag field may refer to theaforementioned external_timeline_reference_flag information. Theexternal_timeline_reference_flag field may be a flag indicating whetherthe corresponding timeline reference information AU includes theexternal_timeline_reference field. That is, the corresponding field mayindicate whether timeline reference information of an external networkis included in timeline reference information AU. The correspondingfield may have a size of 1 bit and have bslbf format.

A suggested_presentation delay_flag field may indicate whethercorresponding timeline reference information AU includes thesuggested_presentation_delay field. That is, the corresponding field mayindicate whether the SPD information is included in timeline referenceinformation AU. The corresponding field may have a size of 1 bit andhave bslbf format. The suggested_presentation_delay field will bedescribed below.

After flag fields, a predetermined size of bits may be reserved forfuture use. In the present embodiment, a 4-bit space may be reserved forfuture use.

The timeline reference information AU may further include informationitems related to timeline reference of an internal network. According toa value of an external_media_URL_flag field, the timeline referenceinformation AU may further include URL information of a streamtransmitted through an external network. In this case, the added fieldswill be described below.

An external_media_URL_length field may be further included in thetimeline reference information AU. The external_media_URL_length fieldmay represent a length of an external_media_URL field in a byte unit.The corresponding field may be an 8-bit field and have uimsbf format.

An external_media_URL field may also be further included in the timelinereference information AU. The external_media_URL field may includeposition information of media transmitted through an external networkand/or unique identification information of the corresponding media. Themedia transmitted through an external network may be accessed throughthese information items. For example, when the media transmitted throughan external network is a media according to DASH, information of MPDURL, MPD ID, etc. of a corresponding MPD of the media may be included inthe external_media_URL field. The corresponding field may have a bitnumber corresponding to a value indicated by the external_mediaURL_length field. In some embodiments, the corresponding field may havea bit number obtained by multiplying a value indicated by theexternal_media_URL_length field by 8.

The timeline reference information AU may further include informationitems related to timeline reference of an internal network. According toa value of the internal_timeline_reference_flag field, the timelinereference information AU may further include additional fields relatedto a timeline of an internal network. In this case, the added fieldswill be described below.

An internal_timeline_reference_format field may be further included inthe timeline reference information AU. Theinternal_timeline_reference_format field may indicate format of timelinereference information of an internal network included in the timelinereference information AU. For example, when the corresponding field hasa value of 0x00, the timeline reference information of the internalnetwork may have media time format, when the corresponding field has avalue of 0x01, the timeline reference information of the internalnetwork may have network time protocol (NTP) format, when thecorresponding field has a value of 0x02, the timeline referenceinformation of the internal network may have PTP format, and when thecorresponding field has a value of 0x03, the timeline referenceinformation of the internal network may have timecode format. When thecorresponding field has a value of 0x04 to 0xFF, the timeline referenceinformation of the internal network may be reserved for future use. Thecorresponding field may have a size of 8 bits and have format uimsbf.

An internal_timeline_reference_timescale_flag field may be furtherincluded in timeline reference information AU. Theinternal_timeline_reference_timescale_flag field may be a flagindicating whether the timeline reference information AU include a timescale of timeline reference information of an internal network. Thecorresponding field may have a size of 1 bit and have bslbf format.

An internal_timeline_reference_length field may be further included intimeline reference information AU. Theinternal_timeline_reference_length field may represent a length oftimeline reference information of an internal network included in thetimeline reference information AU as a byte unit. The correspondingfield may have a size of 7 bits and have uimsbf format. Theinternal_timeline_reference_timescale field may be further included inthe timeline reference information AU.

An internal_timeline_reference_timescale field may represent a timescale of the timeline reference information of the internal networkincluded in the timeline reference information AU in a Hz unit. Thecorresponding field may or may not be present according to a value ofthe aforementioned internal_timeline_reference_timescale_flag field. Thecorresponding field may have a size of 32 bits and have uimsbf format.

An internal_timeline reference field may be further included in timelinereference information AU. The internal_timeline_reference field may havetimeline reference information of an internal network. According to avalue of the corresponding field, a timeline of a media streamtransmitted through the internal network may be reconfigured. Thecorresponding field may have a bit number corresponding to a valueindicated by the internal_timeline_reference_length field. In someembodiments, the corresponding field may have a bit number obtained bymultiplying a value indicated by the internal_timeline_reference_lengthfield by 8.

The timeline reference information AU may further include informationitems related to timeline reference of an external network. According toa value of the external_timeline_reference_flag field, the timelinereference information AU may further include additional fields relatedto the timeline of the external network. In this case, the added fieldswill be described below.

In this case, the timeline reference information AU may further includean external_timeline_reference_format field, anexternal_timeline_reference_timescale_flag field, anexternal_timeline_reference_length field, anexternal_timeline_reference_timescale field, and/or anexternal_timeline_reference field.

Each of the added fields may have information on the media streamtransmitted through an external network. The respective fields maycorrespond to fields of the aforementioned media stream transmittedthrough an internal network and perform similar operations. However, inthis case, each field may have information on an external network butnot an internal network.

That is, the external_timeline_reference_format field, theexternal_timeline_reference_timescale_flag field, theexternal_timeline_reference_length field, and theexternal_timeline_reference_timescale field, andexternal_timeline_reference field may perform similar operations to theaforementioned internal_timeline_reference_format field,internal_timeline_reference_timescale_flag field,internal_timeline_reference_length field,internal_timeline_reference_timescale field, andinternal_timeline_reference field, respectively.

Fields of the media stream transmitted through the external network mayeach indicate format of a media stream transmitted through an externalnetwork, whether time scale information is present, a length, a timescale, and timeline reference, respectively.

The timeline reference field AU may further include fields related tothe SPD. According to a value of the suggested_presentation_delay_flagfield, the timeline reference field AU may further include additionalfields related to the SPD. In this case, the added fields will bedescribed below.

A suggested_presentation_delay_timescale_flag field may be furtherincluded in the timeline reference information AU. Thesuggested_presentation_delay_timescale_flag field may indicate whetherthe suggested_presentation_delay_timescale field is included in thecorresponding timeline reference information AU. Thesuggested_presentation_delay_timescale field will be described below.That is, the corresponding field may indicate whether time scale relatedinformation of the SPD is included in the timeline reference informationAU. When the corresponding field is set to 0 and the time scale relatedinformation of the SPD is not present, a time scale of the SPD may berepresented as a normal clock value. The corresponding field may be a1-bit field and have blsbf format.

A suggested_presentation_delay_length field may be further included inthe timeline reference information AU. The corresponding field mayindicate a length of the SPD in a byte unit. The corresponding field mayhave a size of 7 bits and have uimsbf format.

A suggested_presentation_delay_timescale field may be further includedin the timeline reference information AU. The corresponding field mayindicate a time scale of the SPD in a Hz unit. The corresponding fieldmay or may not be present according to a value of the aforementionedsuggested_presentation_delay_timescale_flag field. The correspondingfield may have a size of 32 bits and have uimsbf format.

A suggested presentation_delay field may be further included in thetimeline reference information AU. The corresponding field may have SPDinformation. That is, the corresponding field may include suggestedpresentation delay information up to consumption time based ongeneration time of a media stream transmitted through an externalnetwork or an internal network. When a timeline of the media stream ofthe internal network/external network is reconfigured using the timelinereference information AU, a value obtained by subtracting a value of thecorresponding field from the timeline reference of each of the internalnetwork/external network may be applied. As such, a timeline to whichthe suggested presentation delay is applied may be configured. Thecorresponding field may have a bit number corresponding to a valueindicated by the aforementioned suggested_presentation_delay_lengthfield. In some embodiments, the corresponding field may have a bitnumber obtained by multiplying a value indicated by thesuggested_presentation_delay_length field by 8. The corresponding fieldmay have uimsbf format.

FIG. 135 is a view illustrating timeline reference information AUincluding, suggested presentation delay (SPD) according to anotherembodiment of the present invention.

The illustrated timeline reference information AU including SPDaccording to another embodiment of the present invention may includetimeline reference information of a plurality of internal networks orexternal networks. As described above, the timeline referenceinformation AU may be used for synchronization of a timeline betweenmedia streams transmitted through different networks.

The AU_identifier field, the AU_length field, thesuggested_presentation_delay_flag field, the external_media_URL_lengthfield, and/or the external_media_URL field are the same as in the abovedescription. The external_media_location_flag field may perform the samefunction as the aforementioned external_media_URL field.

An nb_of_timeline_reference field may indicate the number of timelinereferences included in the corresponding timeline reference informationAU. As described above, timeline reference information AU according tothe present embodiment may have a plurality of timeline referenceinformation items. The corresponding field may have a size of 6 bits andhave uimsbf format.

Timeline reference related information items, the number of which isindicated by the nb_of_timeline_reference field, may be included in thetimeline reference information AU. With respect to each timelinereference, the following fields may be present.

A timeline_reference_type field may indicate a type of a correspondingtimeline reference. For example, when a value of the corresponding fieldis 0, the corresponding timeline reference may be timeline reference ofa media stream transmitted through an internal network. In addition,when a value of the corresponding field is 1, the corresponding timelinereference may be timeline reference of a media stream transmittedthrough an external network. The corresponding field may have a size of1 bit and have bslbf format.

A timeline_reference_identifier field may indicate a unique identifierof corresponding timeline reference. The corresponding field may beallocated to an integer between 0 to 127. The corresponding field mayhave a size of 7 bits and have a uimsbf field.

A timeline_reference_format field may indicate format of thecorresponding timeline reference. The corresponding field may indicateformat of corresponding timeline reference using the same method as theaforementioned internal_timeline_reference_format field andexternal_timeline_reference_format field. The corresponding field mayhave a size of 8 bits and have uimsbf format.

A timeline_reference_timescale_flag field may indicate whetherinformation on a time scale of corresponding timeline reference isincluded in the timeline reference information AU. The correspondingfield may indicate whether time scale related information is presentusing the same method as the aforementionedinternal_timeline_reference_timescale_flag field andexternal_timeline_reference_timescale_flag field. The correspondingfield may have a size of 1 bit and have bslbf format.

A timeline_reference_length field may indicate a length of thecorresponding timeline reference in a byte unit. The corresponding fieldmay indicate a length using the same method as the aforementionedinternal_timeline_reference_length field andexternal_timeline_reference_length field. The corresponding field mayhave a size of 7 bits and have uimsbf format.

The timeline_reference_timescale field may indicate a time scale of thecorresponding timeline reference in a Hz unit. The corresponding fieldmay indicate a time scale using the same method as the aforementionedinternal_timeline_reference_timescale field andexternal_timeline_reference_timescale field. The corresponding field mayhave a size of 32 bits and have uimsbf format.

A timeline_reference field may indicate a timeline reference value ofthe corresponding timeline reference. According to a value of thecorresponding field, a timeline of a media stream transmitted throughthe corresponding internal/external network may be reconfigured. Thecorresponding field may indicate a timeline using the same method as theaforementioned internal_timeline_reference field andexternal_timeline_reference field. The corresponding field may have abit number corresponding to a value indicated by the aforementionedtimeline_reference_length field. In some embodiments, the correspondingfield may have a bit number obtained by multiplying a value indicated bythe timeline_reference_length field by 8. The corresponding field mayuimsbf format.

Fields related to the SPD may have the same structure as theaforementioned structure and may be included in the timeline referenceinformation AU. The suggested_presentation_delay_timescale_flag field,the suggested_presentation_delay_length field, thesuggested_presentation_delay_timescale field, and/or thesuggested_presentation_delay field may be the same as the aforementionedfields with the same names as the above-described fields.

FIG. 136 is a view illustrating an LCT packet structure includingsuggested presentation delay (SPD) according to an embodiment of thepresent invention.

As described above, an LCT packet may transmit timeline referencerelated information. A header of the LCT packet may be extended andinformation for synchronization between media streams transmittedthrough different networks may be transmitted. The proposed structuremay be applied to a packet for a transfer protocol such as a real timeprotocol (RTP). In addition, the proposed structure may be used inassociation with service signaling information suitable for a transferprotocol. The service signaling information may include informationindicating that a corresponding stream transmits timeline reference ofan internal or external network, URL information of media transmittedthrough an external network, the aforementioned various flag informationitems, time scale information of timeline reference, and informationthat is commonly applicable to each packet.

The V field, the C field, the PSI field, the S field, the O field, the Hfield, the Res field, the A field, the B field, the HDR_LEN field, theCP field, the CCI field, the TSI field, and the TOI field are the sameas the aforementioned fields.

A header extension type (HET) field may an extension type of acorresponding LCT packet header. The corresponding field may allocate avalue equal to or less than 127 so as to indicate an extension type ofthe LCT packet header. In the present embodiment, the HET field may havea value of 2 and indicate that an LCT packet header has an extensiontype of EXT_TIME.

A header extension length (HEL) field may indicate a length of acorresponding LCT packet header. The length may be represented in 32-bitword units.

Detailed fields of a USE field may be as follows. The SCT HI field, theSCT Low field, the ERT field, and the SLC field are the same as thedescribed description.

An internal timeline reference high flag (ITR Hi) field may indicatethat an internal timeline reference field of 64 bits is included inextension of a corresponding LCT packet header.

An internal timeline reference low flag (ITR Low) field may indicatethat an internal timeline reference field of 32 bits is included inextension of a corresponding LCT packet header.

An external timeline reference high flag (ETR Hi) field may indicatethat an external timeline reference field of 64 bits is included inextension of a corresponding LCT packet header.

An external timeline reference low flag (ETR Low) field may indicatethat an external timeline reference field of 32 bits is included inextension of a corresponding LCT packet header.

An ITR Scale field may indicate that an internal timeline referencetimescale field of 32 bits is included in extension of a correspondingLCT packet header.

An ETR Scale field may indicate that an external timeline referencetimescale field of 32 bits is included in extension of a correspondingLCT packet header.

An ITR Format field may indicate format of an internal timelinereference field included in extension of a corresponding LCT packetheader. That is, the corresponding field may indicate format of timelinereference of a media stream transmitted through an internal network.

An ETR Format field may indicate format of an external timelinereference field included in extension of a corresponding LCT packetheader. That is, the corresponding field may indicate format of timelinereference of a media stream transmitted through an external network.

When values of the ITR Format field and ETR Format field are each 0x00,corresponding timeline reference may have media time format, when thevalues are each 0x01, the corresponding timeline reference may havenetwork time protocol (NTP) format, when the values are each 0x02, thecorresponding timeline reference may have PTP format, and when thevalues are each 0x03, the corresponding timeline reference may have timecode format. When the values are each 0x04 to 0x0F, the correspondingtimeline reference may be reserved for future use.

An external media URL flag (URL) field may be a flag indicating whetheran external media URL field is present in extension of a correspondingLCT packet header.

A suggested presentation delay flag (SPD) field may be a flag indicatingwhether a suggested presentation delay field is included in extension ofa corresponding LCT packet.

The SPD Scale field may be a flag indicating whether a suggestedpresentation delay timescale field is included in extension of acorresponding LCT packet header. When the corresponding flag field isset to 0, the suggested presentation delay timescale field may not bepresent. In this case, the suggested presentation delay field mayrepresent SPD as a normal clock in a second unit.

The remaining bits of the USE field may be reserved for future use.

The Sender Current Time field, the Expected Residual Time field, and theSession Last Changed field are the same as in the above description.

An Internal Timeline Reference field may indicate timeline referenceinformation of a media stream transmitted through an internal network. Atimeline of a media stream transmitted through an internal network maybe reconfigured through a value of the corresponding field. According toa value of the aforementioned ITR Hi field or ITR Low field, whether thecorresponding field is present may be determined.

An External Timeline Reference field may indicate timeline referenceinformation of a media stream transmitted through an external network. Atimeline of a media stream transmitted through an external network maybe reconfigured through a value of the corresponding field. According toa value of the aforementioned ETR Hi field or ETR Low field, whether thecorresponding field is present may be determined.

An Internal Timeline Reference Timescale field may represent a timescale of timeline reference of a media stream transmitted through aninternal network. Whether the corresponding field is present may bedetermined according to the aforementioned ITR Scale field.

An External Timeline Reference Timescale field may represent a timescale of timeline reference of a media stream transmitted through anexternal network as Hz. Whether the corresponding field is present maybe determined according to the aforementioned ETR Scale field.

An External Media URL field may include position information of mediatransmitted through an external network and/or unique identificationinformation of the corresponding media. The media transmitted throughthe external network may be accessed through the information items. Forexample, when media transmitted through the external network is mediaaccording to DASH, information of MPD URL and MPD ID of correspondingMPD of media may be included in the URL field.

A Suggested Presentation Delay field may include SPD information. Thatis, suggested presentation delay up to consumption time based ongeneration time of a media stream transmitted through an externalnetwork or an internal network may be represented by the correspondingfield. When a timeline of a media stream transmitted through an internalnetwork or an external network, a value obtained by subtracting a valueof the corresponding field from each timeline reference value may beapplied to configure a timeline.

A Suggested Presentation Delay Timescale field may represent a timescale of SPD information represented by the aforementioned suggestedpresentation delay field. The corresponding time scale may be Hz in someembodiments.

The Header Extensions field, the FEC Payload ID field, and the EncodingSymbol (s) field are the same as in the above description.

FIG. 137 is a view illustrating an LCT packet structure includingsuggested presentation delay (SPD) according to another embodiment ofthe present invention.

The present embodiment is similar to the aforementioned LCT packetstructure including the SPD but the Sender Current Time field, theExpected Residual Time field, and/or the Session Last Changed field maybe omitted. As the fields are omitted, the SCT Hi field, the SCT Lowfield, the ERT field, and/or the SLC field as flag fields of thecorresponding fields may also be omitted.

Since timeline reference information through internal/external networksas general purpose of timing information items is already included in anLCT packet, the omitted fields may be omitted for efficiency of the LCTpacket structure.

FIG. 138 is a view illustrating an LCT packet structure includingsuggested presentation delay (SPD) according to another embodiment ofthe present invention.

Extension of an ALC/LCT packet header may have various types. Theextension type of a header may include header extension (EXT_TIME) fortransmitting time related information such as a wall clock of a server.The present embodiment may correspond to an embodiment of EXT_TIME.

In the present embodiment, the HET field, the HEL field, the SCT Hifield, the SCT Low field, the ERT field (or the ERT flag field), the SLCfield (or the SLC flag field), the Res field (or the Res. by LCT field),the SPD field (or the SPD flag field), the Sender Current Time field,the Expected Residual Time field Session Last Changed field, and/or theSuggested Presentation Delay Timescale field are the same as in theabove description.

The LCT packet structure according to the present embodiment may besimilar to an LCT packet structure including the aforementioned SPD butmay further include a TS format field, a TS version field, and/or aTimestamp field. In this diagram, parts except for the extension part ofthe LCT packet structure are omitted.

The TS format field may indicate format of a timestamp field included inthe extension part of the corresponding LCT packet header. For example,when a value of the corresponding field is 0x01, a timestamp may havemedia time format, when the value is 0x02, the timestamp may have NTPformat, when the value is 0x03, the timestamp may have normal playingtime format, when the value is 0x04, the timestamp may have SMPTE timecode format, and when the value is 0x05, the timestamp may have 90KHz-based timestamp format. When a value of the corresponding field is0x00 or 0x06 to 0x0F, the timestamp may be reserved for future use.

The TS version field may indicate a configuration of a timestamp fieldincluded in the extension part of the corresponding LCT packet header.For example, when a value of the corresponding field is 0, a timestampfield may have 32 bits, and when the value is 1, the timestamp field mayhave 64 bits. In some embodiments, lengths of the Suggested PresentationDelay field and Suggested Presentation Delay Timescale field may also bedetermined according to a value of the corresponding field using thesame method. In some embodiments, a separate field may be used torepresent the lengths of the Suggested Presentation Delay field andSuggested Presentation Delay Timescale field.

The SPDT flag field may be the same as the aforementioned SPD scalefield. In some embodiments, when a value of the corresponding field isset to 0, the corresponding field may be set such that the SuggestedPresentation Delay is not present.

The Timestamp field may include timing information related to dataincluded in a payload of the corresponding ALC/LCT packet. For example,a value of the corresponding field may indicate information on time inwhich a first byte of the data included in the payload is decoded. Insome embodiments, the value of the corresponding field may indicatepresentation time information of corresponding data. The correspondingfield may also include a time scale of a timestamp and/or correspondingtime scale based timing information. In some embodiments, thecorresponding field may have a value obtained by adding suggestedpresentation delay (SPD) to timing information such as current time of atransmitting side, encoding time of corresponding media data, and timein which a first byte of corresponding media data is decoded.

The Suggested Presentation Delay field may include SPD information. Thecorresponding field may indicate suggested presentation delay up toconsumption time based on generation time of payload data of acorresponding ALC/LCT packet or an object including the payload data.When a timestamp value of the aforementioned timestamp field is used forsynchronization of a timestamp value, the SPD value may be used. Thatis, a value obtained by adding the SPD value to the timestamp value maybe applied to perform synchronization so as to perform synchronizationto which the suggested presentation delay is applied.

FIG. 139 is a diagram illustrating an extension part of an LCT packetstructure including Suggested Presentation Delay (SPD) according toanother embodiment of the present invention.

The present invention proposes EXT_OBJ_INFO as a new header extensionstructure in an extension part of an ALC/LCT packet structure. The newheader extension structure may include type related information of atransport object and/or timing information related to the correspondingtransport object. The new header extension structure may be included ina header extension field of the ALC/LCT packet header and may be used asa part of a content transport protocol packet header.

The present embodiment corresponds to one embodiment of EXT_OBJ_INFO. Inthe present embodiment, the HET field, the HEL field, the SPD field (orthe SPD flag field), the SDPT flag field, the Timestamp field, theSuggested Presentation Delay field, and/or the Suggested PresentationDelay Timescale field are the same as in the above description.

The LCT packet structure according to the present embodiment is similarto the aforementioned LCT packet structure including the SPD but anObject type field and/or an M field may be further included. In thedrawing, parts except for the extension part of the LCT packet structureare omitted.

The Object Type field may indicate a type of a corresponding transportobject. A transport object type indicated by the corresponding field mayhave a similar value to a payload type value of an RTP packet header. Insome embodiments, a value of the corresponding field may indicatevarious types of a transport object. For example, when a value of thecorresponding field is 0x01, a type of a transport object may be aregular file, when the value is 002, the type of the transport objectmay be HTTP entity format, when the value is 0x03, the type of thetransport object may be AAC-based audio data format, when the value is0x04, the type of the transport object may be H.264-based video dataformat, when the value is 0x05, the type of the transport object may beHEVC-based video data forma, when the value is 0x06, the type of thetransport object may be DASH segment or ISO base media file format, andwhen the value is 0x07, the type of the transport object may be metadataformat. When a value of the corresponding field is 0x00 or 0x07 or more,the type of the transport object may be reserved for future use.

An M field may function as a marker and indicate various objectsaccording to a value of the Object Type field. For example, when anobject type indicated by the Object Type field is a file, the M fieldmay indicate a start or end of the file. In addition, when an objecttype of the Object Type field is video/audio data, the M field mayindicate a start or end of the related data unit. The M field may alsobe referred to as a marker bit field.

In the present embodiment, the Timestamp field, the SuggestedPresentation Delay field, and/or the Suggested Presentation DelayTimescale field may have the same fixed length of 32 bits. 64 bits, andso on. The length may be indicated by a separate length field andindicated by an HEL field.

FIG. 140 is a diagram illustrating an extension part of an LCT packetstructure including Suggested Presentation Delay (SPD) according toanother embodiment of the present invention.

The present invention proposes another structure of the aforementionedEXT_OBJ_INFO. Compared with the aforementioned EXT_OBJ_INFO structure, aTS flag field, a TS format field, and/or a TS version field may befurther included. In the drawing, parts except for the extension part ofthe LCT packet structure are omitted.

TS flag field may be a flag indicating whether a timestamp field ispresent in a corresponding header extension structure. In someembodiments, when a value of the corresponding field is 1, the timestampfield may be present, and when the value is 0, the timestamp field maynot be present. In some embodiments, the meaning of the value of thecorresponding field may be changed.

The TS format field and the TS version field may be the same as in theabove description. However, when the TS flag field is 1, that is, whenthe timestamp field is indicated to be present, the two fields mayindicate format and version of the corresponding timestamp.

The other fields having the same names are the same as in the abovedescription.

FIG. 141 is a diagram illustrating an extension part of an LCT packetstructure including Suggested Presentation Delay (SPD) according toanother embodiment of the present invention.

The present invention proposes another structure of the aforementionedEXT_OBJ_INFO. Compared with the aforementioned EXT_OBJ_INFO structure,an Ext flag field and/or an Extension field may be further included. Inthe drawing, parts except for the extension part of the LCT packetstructure are omitted.

The Ext Flag field may be a flag indicating whether an extension fieldis present in a corresponding header extension structure. In someembodiments, when a value of the corresponding field is 1, the extensionfield may be present, and when the value is 0, the extension field maynot be present. In some embodiments, the meaning of the value of thecorresponding field may be changed.

The Extension field may include additional information related to thecorresponding transport object. For example, the Extension field mayinclude location information of a transport object, and so on. Here, thelocation information of the transport object may be position informationfor obtaining correspond ding information. For example, when a DASHsegment is transmitted to a transport object, a location of thetransport object may be a URL of the DASH segment. In some embodiments,various information items related to the transport object may be addedas a function of extension of the corresponding field.

The other fields having the same names are the same as in the abovedescription.

FIG. 142 is a diagram illustrating an extension part of an LCT packetstructure including Suggested Presentation Delay (SPD) according toanother embodiment of the present invention.

The present invention proposes EXT_MEDIA_TIME as a new header extensionstructure of a header extension part of the ALC/LCT packet structure.The new header extension structure may be included in information oftiming related information, timestamp information, and so on of mediadata. The new header extension structure may be included in a headerextension field of the ALC/LCT packet and used as a portion of a contenttransport protocol packet header, or the like.

The present embodiment corresponds to one embodiment of EXT_MEDIA_TIME.In the case of EXT_MEDIA_TIME, the Object Type field, the M field, andthe TS flag field may be omitted compared with the EXT_OBJ_INFO. In thedrawing, parts except for an extension part of the LCT packet structuremay be omitted.

The TS format field is the same as in the above description. However, inthis case, the corresponding field may indicate that a timestamp has GPStime format according to a value of the field.

The TS version field is the same as in the above description. However,in this case, the corresponding field may indicate whether time scaleinformation of a timestamp is present.

The Ext Flags field may be a set of flag fields of detailed fieldsincluded in the extension field. That is, the corresponding field mayindicate a configuration of the extension field. In some embodiments,like the aforementioned Ext flag field, the corresponding field mayindicate whether the extension field is present. The Extension field mayinclude various information items of information related to a timelinemapped according to a value of the corresponding field.

The other fields having the same names are the same as in the abovedescription.

FIG. 143 is a diagram illustrating an extension part of an LCT packetstructure including Suggested Presentation Delay (SPD) according toanother embodiment of the present invention.

The present invention proposes EXT_TIME_MAP as a new header extensionstructure of a header extension part of the ALC/LCT packet structure.The new header extension structure may be included in a header extensionfield of the ALC/LCT packet and used as a portion of a content transportprotocol packet header, or the like.

The EXT_TIME_MAP may transmit metadata including the aforementionedtimeline component AU or timeline reference information AU to onetransport object. This is because mapping information between twotimelines needs to be transmitted to a receiver when the transportobject needs to be synchronized with another timeline. Through theEXT_TIME_MAP, the corresponding structure may be inserted into theextension part of the header to transmit required information withouttransmission of a separate transport object. When presentation time of apayload of a corresponding packet may be mapped to GPS time and so onusing the transmitted information.

The EXT_TIME_MAP may further include an OTS flag field, an OTS formatfield, an OTS version field, a Location flag field, an Originaltimestamp field, an Location field, and so on.

The TS format field is the same as in the above description but in someembodiments, the corresponding field may indicate that a timestamp isGPS time format.

The OTS Flag field may be a flag indicating whether an originaltimestamp field is present in the extension part of the correspondingpacket header. In some embodiments, when a value of the correspondingfield is 1, the original timestamp field may be present, and when thevalue is 0, the original timestamp field may not be present. In someembodiments, the meaning of the value of the corresponding field may bechanged.

The OTS format field may indicate format of the original timestampfield. In some embodiments, the corresponding field may indicate varioustimestamp formats. For example, a value of the corresponding field is0x01, the timestamp may have media time format, when the value is 0x02,the timestamp may have NTP format, when the value is 0x03, the timestampmay have normal playing time format, when the value is 0x04, thetimestamp may have SMPTE time code format, and when the value is 0x05,the timestamp may have 90 KHz-based timestamp format. When the value ofthe corresponding field is 0x00 or 0x06 to 0x0F, the timestamp may bereserved for future use.

The OTS version field may indicate the version or configuration of theincluded original timestamp field. For example, when a value of thecorresponding field is 0, the original timestamp field may have a sizeof 32 bits, and when the value is 1, the original timestamp may have asize of 16 bits.

The Location Flag field may be a flag indicating whether a locationfield is present in a header part of a corresponding packet header. Insome embodiments, when a value of the corresponding field is 1, thelocation field may be present, and when the value is 0, the locationfield may not be pre sent. In some embodiments, the meaning of the valueof the corresponding field may be changed.

The timestamp field is the same as in the above description. Thecorresponding field may include a timestamp of a transport objectrepresented by the Original Timestamp field and a timestamp of atimeline to be mapped. The timestamp of the corresponding field may bemapped to a timeline represented by the original timestamp field.

The Original Timestamp field may include timestamp information of atransport object having a mapping relationship with a timestamp of thetimestamp field. The timestamp of the corresponding field may be mappedto a timeline represented by the timestamp field. In some embodiments,the corresponding field may have a value obtained by adding suggestedpresentation delay (SPD) to timing information of current time of atransmitting side, encoding time of corresponding media data, and timein which a first byte of the corresponding media data is decoded.

The location field may include location information of data related to atimeline to be mapped, and so on. For example, when a timestamp ismapped to a timeline of a specific DASH segment, URL information of theDASH segment may be included in the corresponding field.

The other fields having the same names are the same as in the abovedescription.

In order to perform a function of a header or extension part of theheader of the aforementioned LCT packet, a presentation time header(EXT_ROUTE_PRESENTATION_TIME) of ROUTE may be used. In some embodiments,in order to perform a function of a header or extension part of theheader of the aforementioned LCT packet, an EXT_TIME header of RFC 5651of IETF “Layered Coding Transport (LCT) Building Block,” may also beused.

The header or extension parts of the header of the aforementioned LCTpacket may correspond to one embodiment of EXT_ROUTE_PRESENTATION_TIME.In some embodiments, the header or extension parts of the header of theaforementioned LCT packet may correspond to one embodiment of anEXT_TIME header. The header or extension parts of the header of theaforementioned LCT packet may transmit timing related information asdescribed above.

An LCT packet header according to another embodiment of the presentinvention may represent third, fourth, and fifth octets a 64-bit NTPtimestamp. The header of the present embodiment may have an HET fieldand may also have a fixed length. A value of the header according to thepresent embodiment may be greater than the SCT. The LCT packet headeraccording to the present embodiment may have a size of total of 4 bytes.

An LCT packet header according to another embodiment of the presentinvention may have all values of a 64-bit NTP timestamp. The headeraccording to the present embodiment may have an HET field and/or an HELfield. The LCT packet header according to the present embodiment mayhave a size of total of 12 bytes. Accordingly, the remaining bit numbermay be reserved for future use.

FIG. 144 is a diagram illustrating a method of transmitting broadcastcontent according to an embodiment of the present invention.

A method of receiving broadcast content according to an embodiment ofthe present invention may include generating a first media stream ofbroadcast content, generating a second media stream of the broadcastcontent, transmitting the first media stream through a broadcastnetwork, receiving a request for the second media stream, and/ortransmitting the second media stream to a receiver through the Internet.

First, the first media stream of the broadcast content may be generated.This procedure may be performed by the first module. Here, the firstmedia stream may be a media stream transmitted through a broadcastnetwork. In the aforementioned embodiment, a media stream transmittedthrough an internal network may correspond to the first media stream.The first media stream may be formed by continuously arranging aplurality of packets. Among these, at least one packet may include timeinformation. Here, the information is an integrated concept indicatingall information items related to time. In some embodiments, the timeinformation may correspond to the aforementioned extension part of thetiming related LCT packet header, the timeline reference information AU,timeline component AU, and so on.

The second media stream of the aforementioned broadcast content may begenerated. This procedure may be performed by the second module. Here,the second media stream may be a media stream transmitted through theInternet. In the aforementioned embodiment, a media stream transmittedthrough an external network may correspond to the second media stream.The first module and the second module may be integrated into each otherand may operate as one module.

The generated first media stream may be transmitted to a receiving sidethrough a broadcast network. In addition, the generated second mediastream may be transmitted to the receiving side through the Internet.The fourth module may receive a request for the second media stream fromthe receiver and transmit a corresponding media stream to the receivingside according to the request. This request may be performed accordingto the aforementioned external_media_URL field.

In the method of transmitting broadcast content according to anotherembodiment of the present invention, packets of the aforementioned firstmedia stream may include an extension header including theaforementioned time information. The extension header may be anextension part of the aforementioned LCT packet header. Here, theaforementioned time information may include timestamp informationindicating presentation time of the first media stream. The timestampinformation may correspond to the aforementioned timestamp field.

In the method of transmitting broadcast content according to anotherembodiment of the present invention, the aforementioned extension headermay include only a portion of the timestamp. As described above, anextension header according to an embodiment of the present invention mayrepresent third, fourth, and fifth octets a 64-bit NTP timestamp. Whenthe aforementioned extension header includes only a portion of thetimestamp, the extension header may include only some octets of thetimestamp.

In the method of transmitting broadcast content according to anotherembodiment of the present invention, the aforementioned extension headermay further include timestamp information indicating presentation timeof the second media stream. Here, a timestamp indicating presentationtime of the second media stream may refer to a timestamp represented bythe aforementioned original timestamp field. That is, as describedabove, the extension header may further include an original timestampfield.

In the method of transmitting broadcast content according to anotherembodiment of the present invention, the aforementioned extension headermay further include information on suggested presentation delay up toconsumption time from generating time of the first media stream. Here,the information on the suggested presentation delay may refer to theaforementioned SPD. The extension header may further include SuggestedPresentation Delay field. The receiver may add the SPD to the timestampvalue and perform synchronization to which the SPD is applied.

In the method of transmitting broadcast content according to anotherembodiment of the present invention, a timestamp indicating presentationtime of the aforementioned first media stream may have a timestamp valueto which the SPD is already applied. The timestamp field may include avalue obtained by adding the SPD value to the timestamp value.Accordingly, the presentation time to which the SPD is applied may be represented.

In the method of transmitting broadcast content according to anotherembodiment of the present invention, the aforementioned packets mayinclude timeline reference information items. Reference informationitems may include first timeline reference information for configuring atimeline of the first media stream and/or second timeline referenceinformation for configuring a timeline of the second media stream. Eachof the timeline reference information items may be used to reconfigure atimeline of each media stream. The timeline references may be mapped toconfigure a synchronized timeline. The timeline may be used tosynchronize media streams transmitted through different networks.Packets having this payload may be timeline reference information AUpacketized using the same as general packets. In some embodiments, thesepackets may be timeline component AU.

In the method of transmitting broadcast content according to anotherembodiment of the present invention, a payload of the aforementionedpackets may further include information on suggested presentation delay.When the suggested presentation delay information may indicate time upto consumption time from generation time of the first media streamand/or the second media stream. The meaning may be changed in someembodiments. As described above, the SPD value may be subtracted fromthe timeline reference value to reconfigure a timeline to which the SPDvalue is applied.

In the method of transmitting broadcast content according to anotherembodiment of the present invention, the aforementioned timelinereference information items may have a timeline reference value to whichthe SPD value is already applied.

In the method of transmitting broadcast content according to anotherembodiment of the present invention, the aforementioned first mediastream may be a video stream of the aforementioned broadcast content andthe second media stream may be an audio stream of the broadcast content.

A method of receiving broadcast content according to an embodiment ofthe present invention will be described. The method of receivingbroadcast content according to an embodiment of the present invention isnow shown.

The method of receiving broadcast content according to an embodiment ofthe present invention may include receiving a first media stream througha broadcast network, receiving a second media stream through theInternet according to a request through URL information, configuring atimeline of the first and second media streams, mapping the configuredtimelines and performing synchronization of timelines of the two mediastreams, and/or reproducing corresponding media data at specific timethrough a timestamp value.

The receiving of the first media stream may be performed by a firstreceiving module. The receiving of the second media stream through theInternet according to the request through the URL information may beperformed by the second receiving module. The configuring of thetimeline of the first and second media streams may be performed by athird receiving module. The mapping of the configured timelines andperforming of the synchronization of the timelines of the two mediastreams may be performed by a fourth receiving module. The reproducingof the corresponding media data at specific time through the timestampvalue may be performed by a fifth receiving module. Here, the thirdreceiving module and the fourth receiving module may be integrated intoeach other and may operated as one module.

Each timeline may be reconfigured according to timeline referenceinformation of timeline reference information AU in a media stream. Inthis case, each timeline may be mapped so as to synchronize the mediastreams. The SPD information that is transmitted together may be used toreconfigure a timeline to which the SPD is applied. In this case, a SPDvalue may be subtracted from the timeline reference value to apply theSPD.

In addition, each packet header of the media stream may includetimestamp information. The timestamp information may be used torecognize presentation time of each media stream. The SPD informationthat is transmitted together may be used to acquire a time stamp valueto which the SPD is applied. In this case, the SPD value may be added tothe timestamp value to acquire presentation time of corresponding mediadata to which the SPD is applied.

In some embodiments, the aforementioned operations may be omitted orreplaced by other operations that perform the same/similar operations.

FIG. 145 is a diagram illustrating an apparatus for transmittingbroadcast content according to an embodiment of the present invention.

The apparatus for transmitting broadcast content according to anembodiment of the present invention may include a first module, a secondmodule, a third module, and/or a fourth module.

The modules may be the same as the respective aforementioned moduleshaving the same names. The first module may perform generating of thefirst media stream of the broadcast content. The second module mayperform generating of the second media stream of the broadcast content.The third module may perform transmitting of the first media streamthrough a broadcast network. The fourth module may perform receiving arequest for the second media stream and/or transmitting the second mediastream through the Internet.

An apparatus for receiving broadcast content according to an embodimentof the present invention will be described. The apparatus for receivingbroadcast content is not shown.

The apparatus for receiving broadcast content according to an embodimentof the present invention may include a first receiving module, a secondreceiving module, a third receiving module, a fourth receiving module,and/or a fifth receiving module. Each module may be the same as theaforementioned module having the same name.

In some embodiments, the aforementioned modules may be omitted and/orreplaced by other modules that perform the same/similar operation.

The aforementioned first receiving module, second receiving module,third receiving module, fourth receiving module, and/or fifth receivingmodule may be processors for executing consecutive procedures stored ina memory. In addition, the aforementioned first module, second module,third module, fourth module, first receiving module, second receivingmodule, third receiving module, fourth receiving module, and/or fifthreceiving module may be hardware elements positioned inside/outside theapparatus.

The modules or units may be processors for executing consecutiveprocesses stored in a memory (or a storage unit). The steps described inthe above-described embodiments may be performed by hardware/processors.The modules/blocks/units described in the above-described embodimentsmay operate as hardware/processors. The methods proposed by the presentinvention may be executed as code. This code may be written in aprocessor-readable storage medium and may be read by the processorprovided by an apparatus.

Although the description of the present invention is explained withreference to each of the accompanying drawings for clarity, it ispossible to design new embodiment(s) by merging the embodiments shown inthe accompanying drawings with each other. In addition, if a recordingmedium readable by a computer, in which programs for executing theembodiments mentioned in the foregoing description are recorded, isdesigned in necessity of those skilled in the art, it may belong to thescope of the appended claims and their equivalents.

An apparatus and method according to the present invention may benon-limited by the configurations and methods of the embodimentsmentioned in the foregoing description. In addition, the embodimentsmentioned in the foregoing description can be configured in a manner ofbeing selectively combined with one another entirely or in part toenable various modifications.

In addition, a method according to the present invention can beimplemented with processor-readable codes in a processor-readablerecording medium provided to a network device. The processor-readablemedium may include all kinds of recording devices capable of storingdata readable by a processor. The processor-readable medium may includeone of ROM, RAM, CD-ROM, magnetic tapes, floppy discs, optical datastorage devices, and the like for example and also include such acarrier-wave type implementation as a transmission via Internet.Furthermore, as the processor-readable recording medium is distributedto a computer system connected via network, processor-readable codes canbe saved an executed according to a distributive system.

Although the preferred embodiments of the present invention have beendisclosed for illustrative purposes, those skilled in the art willappreciate that various modifications, additions and substitutions arepossible, without departing from the scope and spirit of the inventionas disclosed in the accompanying claims. Such modifications should notbe individually understood from the technical spirit or prospect of thepresent invention.

Both apparatus and method inventions are mentioned in this specificationand descriptions of both of the apparatus and method inventions may becomplementarily applicable to each other.

Those skilled in the art will appreciate that various modifications andvariations can be made in the present invention without departing fromthe spirit or scope of the invention described in the appended claims.Accordingly, the present invention are intended to include themodifications and variations of the present invention provided withinthe appended claims and equivalents thereof.

Both apparatus and method inventions are mentioned in this specificationand descriptions of both of the apparatus and method inventions may becomplementarily applicable to each other.

MODE FOR INVENTION

Various embodiments have been described in the best mode for carryingout the invention.

INDUSTRIAL APPLICABILITY

The present invention is available in a series of broadcast signalprovision fields.

It will be apparent to those skilled in the art that variousmodifications and variations can be made in the present inventionwithout departing from the spirit or scope of the inventions. Thus, itis intended that the present invention covers the modifications andvariations of this invention provided they come within the scope of theappended claims and their equivalents.

1. A method for transmitting broadcast content, the method comprising:generating a first media stream of broadcast content by a first module,the first media stream comprising a plurality of packets and at leastone of the packets comprising time information; generating a secondmedia stream of the broadcast content by a second module; transmittingthe first media stream through a broadcast network by a third module;receiving a request for the second media stream from a receiver by afourth module; and transmitting the second media stream to a receiverthrough the Internet by the fourth module.
 2. The method according toclaim 1, wherein: the at least one packet comprises an extension headercomprising the time information; and the time information comprisestimestamp information indicating presentation time of the first mediastream.
 3. The method according to claim 2, wherein the extension headercomprises only a portion of the timestamp.
 4. The method according toclaim 2, wherein the extension header further comprises timestampinformation indicating presentation time of the second media stream. 5.The method according to claim 2, wherein the extension header furthercomprises information on suggested presentation delay up to consumptiontime from generating time of the first media stream.
 6. The methodaccording to claim 5, wherein the timestamp indicating presentation timeof the first media stream indicates a presentation time value of thefirst media stream to which the suggested presentation delay is applied.7. The method according to claim 2, wherein a payload of the at leastone packet comprises first timeline reference information forconfiguring a timeline of the first media stream and second timelinereference information for configuring a timeline of the second mediastream.
 8. The method according to claim 7, wherein the payload of theat least one packet further comprises information on suggestedpresentation delay up to consumption time of generating time of thefirst media stream and the second media stream.
 9. The method accordingto claim 8, wherein the first timeline reference information and thesecond timeline reference information have a value to which thesuggested presentation delay is applied.
 10. The method according toclaim 1, wherein: the first media stream is a video stream of thebroadcast content; and the second media stream is an audio stream of thebroadcast content.
 11. An apparatus for transmitting broadcast content,the apparatus comprising: a first module configured to generate a firstmedia stream of broadcast content, the first media stream comprising aplurality of packets and at least one of the packets comprising timeinformation; a second module configured to generate a second mediastream of the broadcast content; a third module configured to transmitthe first media stream through a broadcast network; and a fourth moduleconfigured to receive a request for the second media stream from areceiver and to transmit the second media stream to a receiver throughthe Internet.
 12. The apparatus according to claim 11, wherein: the atleast one packet comprises an extension header comprising the timeinformation; and the time information comprises timestamp informationindicating presentation time of the first media stream.
 13. Theapparatus according to claim 12, wherein the extension header comprisesonly a portion of the timestamp.
 14. The apparatus according to claim12, wherein the extension header further comprises timestamp informationindicating presentation time of the second media stream.
 15. Theapparatus according to claim 12, wherein the extension header furthercomprises information on suggested presentation delay up to consumptiontime from generating time of the first media stream.
 16. The apparatusaccording to claim 15, wherein the timestamp indicating presentationtime of the first media stream indicates a presentation time value ofthe first media stream to which the suggested presentation delay isapplied.
 17. The apparatus according to claim 12, wherein a payload ofthe at least one packet comprises first timeline reference informationfor configuring a timeline of the first media stream and second timelinereference information for configuring a timeline of the second mediastream.
 18. The apparatus according to claim 17, wherein the payload ofthe at least one packet further comprises information on suggestedpresentation delay up to consumption time of generating time of thefirst media stream and the second media stream.
 19. The apparatusaccording to claim 18, wherein the first timeline reference informationand the second timeline reference information have a value to which thesuggested presentation delay is applied.
 20. The apparatus according toclaim 11, wherein: the first media stream is a video stream of thebroadcast content; and the second media stream is an audio stream of thebroadcast content.